Showing papers on "Stark effect published in 2003"
TL;DR: Balmer-alpha, -beta and -gamma lines have been calculated using computer simulations including ion dynamics effects for equilibrium and non-equilibrium conditions as discussed by the authors, and the results obtained allow us to supply diagnostic maps based on the widths of those lines, as well as the Stark broadened full line profiles and the dipolar correlation functions obtained in the simulations.
452 citations
TL;DR: In this paper, the authors present a series of microscopic studies of electrical transport through individual molecules with metallic contacts, and analyze the device characteristics in terms of the charge and potential response of these atomic groups to the perturbation induced by the metal-molecule coupling and the applied bias voltage, which are modeled using a first-principles based self-consistent matrix Green's function (SCMGF) method.
Abstract: We present the first in a series of microscopic studies of electrical transport through individual molecules with metallic contacts. We view the molecules as ``heterostructures'' composed of chemically well-defined atomic groups, and analyze the device characteristics in terms of the charge and potential response of these atomic groups to the perturbation induced by the metal-molecule coupling and the applied bias voltage, which are modeled using a first-principles based self-consistent matrix Green's function (SCMGF) method. As the first example, we examine the devices formed by attaching two benzene-based molecular radicals---phenyl dithiol (PDT) and biphenyl dithiol (BPD)---symmetrically onto two semi-infinite gold electrodes through the end sulfur atoms. We find that both molecules acquire a fractional number of electrons with similar magnitude and spatial distribution upon contact with the electrodes. The charge transfer creates a potential barrier at the metal-molecule interface that modifies significantly the frontier molecular states depending on the corresponding electron density distribution. For both molecules, the metal Fermi level is found to lie closer to the highest-occupied-molecular-orbital (HOMO) than to the lowest-unoccupied-molecular-orbital (LUMO). Transmission in the HOMO-LUMO gap for both molecules is due to the metal-induced gap states arising from the hybridization of the metal surface states with the occupied molecular states. Applying a finite bias voltage leads to only minor net charge injection due to the symmetric device structure assumed in this work. But as current flows, the electrons within the molecular junction redistribute substantially, with resistivity dipoles developing in the vicinity of potential barriers. Only the delocalized $\ensuremath{\pi}$ electrons in the benzene ring can effectively screen the applied electric field. For the PDT molecule, the majority of the bias voltage drops at the metal-molecule interface. But for the BPD molecule, a significant amount of the voltage also drops in the molecule core. The field-induced modification of the molecular states (the static Stark effect) becomes significant as the bias voltage increases beyond the linear-transport region. A bias-induced reduction of the HOMO-LUMO gap is observed for both molecules at large bias. The Stark effect is found to be stronger for the BPD molecule than the PDT molecule despite the longer length of the former. For both molecules, the peaks in the conductance are due to electron transmission through the occupied rather than the unoccupied molecular states. The calculation is done at room temperature, and we find that the thermionic-emission contribution to the current-voltage characteristics of both molecules is negligible.
364 citations
TL;DR: Vibrational Stark effect spectroscopy provides a direct measurement of the Stark tuning rate and allows a quantitative interpretation of frequency shifts, which provide the primary information needed to design amino acid analogues or labels to act as probes of local environments in proteins.
Abstract: Infrared spectroscopy is widely used to probe local environments and dynamics in proteins. The introduction of a unique vibration at a specific site of a protein or more complex assembly offers many advantages over observing the spectra of an unmodified protein. We have previously shown that infrared frequency shifts in proteins can arise from differences in the local electric field at the probe vibration. Thus, vibrational frequencies can be used to map electric fields in proteins at many sites or to measure the change in electric field due to a perturbation. The Stark tuning rate gives the sensitivity of a vibrational frequency to an electric field, and for it to be useful, the Stark tuning rate should be as large as possible. Vibrational Stark effect spectroscopy provides a direct measurement of the Stark tuning rate and allows a quantitative interpretation of frequency shifts. We present vibrational Stark spectra of several bond types, extending our work on nitriles and carbonyls and characterizing four additional bond types (carbon-fluorine, carbon-deuterium, azide, and nitro bonds) that are potential probes for electric fields in proteins. The measured Stark tuning rates, peak positions, and extinction coefficients provide the primary information needed to design amino acid analogues or labels to act as probes of local environments in proteins.
239 citations
TL;DR: In this article, the Stark shift was used to tune the excitonic energy levels of a single quantum dot into resonance with a narrow-band laser line at 4.2 K. Relative changes in transmission can be detected this way down to one part per million.
Abstract: Excitonic interband optical transitions within single InAs self-assembled quantum dots have been directly observed in a transmission experiment at 4.2 K. Using Stark shift, the excitonic energy levels of a single quantum dot are tuned into resonance with a narrow-band laser line. The Stark shift is also modulated at low frequencies. Relative changes in transmission can be detected this way down to one part per million. The oscillator strength as well the homogeneous linewidth of the transition is obtained.
156 citations
TL;DR: In situ observation of laser-induced fluorescence along the beam propagation path allows for detailed characterization of longitudinal phase-space manipulation of OH molecules through the Stark effect by precisely sequenced inhomogeneous electric fields.
Abstract: We report bunching, slowing, and acceleration of a supersonically cooled beam of diatomic hydroxyl radicals (OH). In situ observation of laser-induced fluorescence along the beam propagation path allows for detailed characterization of longitudinal phase-space manipulation of OH molecules through the Stark effect by precisely sequenced inhomogeneous electric fields.
138 citations
TL;DR: This work considers the creation of a field-free "switched" wave packet through adiabatic turn-on and sudden turn-off of a strong dynamic Stark interaction, and identifies two limiting cases for such wave packets.
Abstract: The dynamic Stark effect due to a strong nonresonant but nonionizing laser field provides a route to quantum control via the creation of novel superposition states. We consider the creation of a field-free "switched" wave packet through adiabatic turn-on and sudden turn-off of a strong dynamic Stark interaction. There are two limiting cases for such wave packets. The first is a Raman-type coupling, illustrated by the creation of field-free molecular axis alignment. An experimental demonstration is given. The second case is that of dipole-type coupling, illustrated by the creation of charge localization in an array of quantum wells.
125 citations
TL;DR: In this article, a photo-induced charged exciton was used to produce biexponential decay dynamics for CdSe quantum dot exciton recombination, which is composed of an intrinsic band edge exciton decay and a photoinduced charged entanglement, and the nearly identical radiative lifetime of both intrinsic and extrinsic decays scale with the cube of the size.
Abstract: In solution, CdSe quantum dot exciton recombination is composed of an intrinsic band edge exciton decay and a photoinduced charged exciton, which produces the observation of biexponential decay dynamics. The nearly identical radiative lifetimes of both intrinsic and extrinsic decays scale with the cube of the size, and the nonradiative rate for the intrinsic decay follows the energy gap law, while the charged exciton exhibits strong lattice perturbations arising from Frolich coupling to optical phonons. The charged exciton, which arises from recombination in a particle that has a photo-induced trapped carrier has a temporally resolved Stark shift of ∼20 meV.
116 citations
TL;DR: In this article, the 1S0-3P1 transition of Sr atoms confined in a one-dimensional optical lattice was investigated and the wavelength where the Stark shifts for both states coincide was determined.
Abstract: Recoil-free as well as Doppler-free spectroscopy was demonstrated on the 1S0-3P1 transition of Sr atoms confined in a one-dimensional optical lattice. By investigating the wavelength and polarization dependence of the ac Stark shift acting on the 1S0 and 3P1(m(J)=0) states, we determined the wavelength where the Stark shifts for both states coincide. This Stark-free optical lattice, allowing the purturbation-free spectroscopy of trapped atoms, may keep neutral-atom based optical standards competitive with single-ion standards.
113 citations
TL;DR: The voltage sensitivity of hemicyanine dyes ANNine-6 and ANNINE-5 with anellated benzene rings and without free CC single and double bonds is studied in Retzius neurons from Hirudo medicinalis to find the ANNINE dyes are the most efficient fluorescent probes of neuronal activity on the benthic membrane.
Abstract: The voltage sensitivity of hemicyanine dyes ANNINE-6 and ANNINE-5 with anellated benzene rings and without free CC single and double bonds is studied in Retzius neurons from Hirudo medicinalis. For comparison, biaryl hemicyanine BNBIQ and styryl hemicyanines di-4-ANEPBS and RH-421 are investigated. Fluorescence spectra are recorded by an independent variation of the wavelengths of excitation and emission at two defined membrane voltages. With extracellular staining, a positive change in the intracellular voltage shifts all excitation spectra to the blue. That modulation is assigned to a molecular Stark effect that increases in the series RH-421, di-4-ANEPBS, BNBIQ, ANNINE-5, and ANNINE-6 with displacements of elementary charge by 0.24, 0.43, 0.51, 0.65, and 0.81 nm across the membrane. For BNBIQ, ANNINE-5, and ANNINE-6, an almost identical blue shift is observed for the emission that is also assigned to a Stark effect. The ANNINE dyes are the most efficient fluorescent probes of neuronal activity on the b...
97 citations
TL;DR: A detailed analysis of the optical properties of Eu3+ ions in calcium diborate glasses has been performed in order to correlate them with the local environment of the lanthanide ions in these glasses as mentioned in this paper.
Abstract: A detailed analysis of the optical properties of Eu3+ ions in calcium diborate glasses has been performed in order to correlate them with the local environment of the lanthanide ions in these glasses. From the excitation and emission spectra under broadband excitation the energy level diagram of the Eu3+ ion and the atomic parameters have been obtained. Moreover, it is found that the Eu3+ ions are predominantly bonded with the bridging and non-bridging oxygens of different borate groups containing the BO3 units. Under site selective excitation in the 7 F 0 → 5 D 0 inhomogeneously broadened peak, valuable information about the splitting of the 7F1 and 7F2 levels and the lifetime of the 5D0 level has been obtained as a function of the excitation wavelength. The linewidth of the low-energy components of the 5 D 0 → 7 F 1 emission shows an increase with the splitting of this level that can be well explained considering non-radiative de-excitation processes towards lower 7F1 Stark levels. From the splitting of the 7F1 and 7F2 levels, the second and fourth rank crystal-field parameters have been calculated as a function of the excitation wavelength. The observed behaviour suggests the existence of an unique class of site for the Eu3+ ions, with a large range of values for the crystal-field strength parameter NV(B2q), from 1000 to 3200 cm−1, that includes weak, medium and strong crystal-field environments for the Eu3+ ions in the calcium diborate glass. The J-mixing is shown to play a relevant role in these calculations for medium and strong crystal-field environments, i.e., for values of the crystal-field strength parameter NV(B2q) over 1400 cm−1.
93 citations
TL;DR: In this article, the effect of three-body recombination on atomic titanium temporal distribution has been explained, as determined by Stark effect, for the estimation of the three body recombination rate constant, and the quasi-equilibrium state of the laser-induced plasma has been established on the basis of the failure of Saha balance equation.
12 May 2003
TL;DR: In this paper, the dipole interaction (Stark effect) of a polar molecule allows one to use an inhomogeneous electric field to bend and focus a neutral beam in a transport line.
Abstract: The dipole interaction (Stark effect) of a polar molecule allows one to use an inhomogeneous electric field to bend and focus a neutral beam in a transport line. The dependence of the optics on the Stark potential energy is discussed and we describe the type of multipole-field lenses that are needed. The special features that differ from charged particle optics are discussed. The RMS envelope equations are used to design a rotational-state separator to be built at LBNL. Its performance is simulated using the non-linear trajectory equations (with off-energy molecules included) and we find good state selection.
TL;DR: A quantitative low-temperature scanning tunneling spectroscopy study on the Ag(111) surface state over an unprecedented range of currents through which the electric field in the tunnel junction of the microscope is tuned, and it is shown that in STS a sizable Stark effect causes a shift of the surface-state binding energy E0.
Abstract: We report a quantitative low-temperature scanning tunneling spectroscopy (STS) study on the Ag(111) surface state over an unprecedented range of currents (50 pA to $6\text{ }\ensuremath{\mu}\mathrm{A}$) through which we can tune the electric field in the tunnel junction of the microscope. We show that in STS a sizable Stark effect causes a shift of the surface-state binding energy ${E}_{0}$. Data taken are reproduced by a one-dimensional potential model calculation, and are found to yield a Stark-free energy ${E}_{0}$ in agreement with recent state-of-the-art photoemission spectroscopy measurements.
TL;DR: The spatial characterization of laser-induced plasmas, including their temperature, electron density, and relative atom density, has been carried out by emission spectroscopy using an imaging spectrometer equipped with an intensified CCD detector with spatial resolution.
Abstract: The spatial characterization of laser-induced plasmas, including their temperature, electron density, and relative atom density, has been carried out by emission spectroscopy. The plasmas were generated with iron samples in air and argon at atmospheric pressure. An imaging spectrometer equipped with an intensified CCD detector procured spectra with spatial resolution. The plasma characterization was made at three temporal gates (2–3, 5–6, and 9–11 µs) to permit the plasma’s evolution to be studied. A deconvolution procedure was developed to transform the measured intensity, integrated along the line of sight, into the radial distribution of emissivity. Temperature and electron density distributions were obtained under the assumption of local thermodynamic equilibrium and Stark broadening of the emission lines. The relative atom density distributions in the plasma of the Fe atoms arising from the sample and of the Ar atoms arising from the ambient gas were determined and evidenced an important interaction between the plasma and the surrounding atmosphere.
TL;DR: This work modulated a 70 fs laser pulse with a period on the time scale of the vibrational motion by mixing the signal and idler of an optical parametric amplifier to launch a vibrational wave packet on the ground state of H2 or D2.
Abstract: Intense, nonresonant laser fields produce Stark shifts that strongly modify the potential energy surfaces of a molecule. A vibrational wave packet can be guided by this Stark shift if the laser field is appropriately modulated during the wave packet motion. We modulated a 70 fs laser pulse with a period on the time scale of the vibrational motion (approximately 10 fs) by mixing the signal and idler of an optical parametric amplifier. We used ionization of H2 or D2 to launch a vibrational wave packet on the ground state of H2(+) or D2(+). If the laser intensity was high as the wave packet reached its outer turning point, the Stark shift allowed the molecule to dissociate through bond softening. On the other hand, if the field was small at this critical time, little dissociation was measured. By changing the modulation period, we achieved control of the dissociation yield with a contrast of 90%.
TL;DR: In this article, the Stark broadening of lines spontaneously emitted by a plasma was used to determine the electron density and temperature in a discharge produced at atmospheric pressure using a direct method.
Abstract: This paper discusses the possibility of determining, at the same time, both the electron density and temperature in a discharge produced at atmospheric pressure using the Stark broadening of lines spontaneously emitted by a plasma. This direct method allows us to obtain experimental results that are in good agreement with others previously obtained for the same type of discharge. Its advantages and disadvantages compared to other direct methods of diagnostics, namely Thomson scattering, are also discussed.
TL;DR: In this paper, angle-resolved electron-momentum distributions from 800-nm short-pulse laser ionization of argon and compare their data with numerical solutions of the time-dependent Schrodinger equation are used.
Abstract: We record angle-resolved electron-momentum distributions from 800-nm short-pulse laser ionization of argon and compare our data with numerical solutions of the time-dependent Schrodinger equation. A model potential of argon and the single active electron approximation are used. The calculation shows quantitative agreement in all dominant features of the experimental results. The energy and angular distributions of the photoelectrons, together with numerical simulations, allow us to identify the multiple processes involved during the interaction, such as channel switching, multiphoton resonant and nonresonant ionization, and ac Stark splitting.
TL;DR: The results favor a model that locates both beta-carotene molecules at the same side of the complex, and the red-shifted Stark spectra can be explained by a mixing of exciton states with a charge-transfer state of about equal energy.
Abstract: We present an electric field modulated absorption spectroscopy (Stark effect) study of isolated photosystem II reaction center complexes, including a preparation in which the inactive pheophytin HB was exchanged for 131-deoxo-131-hydroxy-pheophytin. The results reveal that the Stark spectrum of the Qx and Qy transitions of the pheophytins has a second-derivative line shape, indicating that the Stark effect is dominated by differences in the dipole moment between the ground and the electronically excited states of these transitions (Δμ). The Δμ values for the Qx and Qy transitions of HB are small (Δμ = 0.6−1.0 D f-1), whereas that of the Qx transition of the active pheophytin HA is remarkably large (Δμ = 3 D f-1). The Stark spectrum of the red-most absorbing pigments also shows a second-derivative line shape, but this spectrum is considerably red-shifted as compared to the second derivative of the absorption spectrum. This situation is unusual but has been observed before in heterodimer special pair mutant...
TL;DR: In this article, a low-temperature photoluminescence study of 4H/3C/4H-SiC single quantum well is presented. But the authors focus on the spontaneous polarization difference between 3C- and 4H -SiC bilayers.
Abstract: We report a low-temperature photoluminescence study of 4H/3C/4H-SiC single quantum wells. A quantum well consists of thirteen 3C-SiC bilayers as displayed in a high-resolution transmission electron microscope image. The optical emission energy of the quantum well is more than 200 meV below the exciton band gap of bulk 3C-SiC. A strong internal electric field on the order of 1 MV/cm leads to the large redshift of the emission energy due to the quantum-confined Stark effect. The origin of this field is discussed in terms of the spontaneous polarization difference between 3C- and 4H-SiC.
TL;DR: In this paper, the rotational spectra of quinoline and isoquinoline have been observed in the centimeter- and millimeter-wave regions, and the ground states of both molecules were determined from Stark effect measurements.
TL;DR: With the ultrahigh time resolution of a femtosecond laser pulse, one can directly measure the absolute value of the transition dipole moment between any kinds of molecular states by this kind of Autler-Townes splitting.
Abstract: We report for the first time the proper conditions to observe Autler-Townes splitting (ac-Stark splitting) from vibrationally coherent states belonging to the different electronic terms of a diatomic molecule. Wave packet dynamics simulations demonstrate that such a process is feasible by multiphoton resonance ionization of the molecule ${\mathrm{N}\mathrm{a}}_{2}$ with a single ultrashort intense laser pulse. With the ultrahigh time resolution of a femtosecond laser pulse, one can directly measure the absolute value of the transition dipole moment between any kinds of molecular states by this kind of Autler-Townes splitting, which is a function of the internuclear distance $R$.
TL;DR: In this paper, density functional theory was used to calculate the vibrational Stark tuning rate of a variety of nitriles and carbonyls in quantitative agreement with experimental values with a correction factor of f = 1.1 for the local electric field.
Abstract: Density functional theory (DFT) has been used to calculate the vibrational Stark tuning rates of a variety of nitriles and carbonyls in quantitative agreement with experimental values with a correction factor of f=1.1 for the local electric field. These calculations show that the vibrational Stark tuning rate has an anharmonic contribution and a contribution due to geometric distortions caused in the molecules due to the applied electric field. The anharmonic and geometric distortion components of the vibrational Stark tuning rate were calculated by the frequency dependence of the CN or CO stretching mode with varying applied electric fields by using the optimized structure in zero applied field or allowing the structure to optimize in the applied electric field, respectively. The changes in the calculated frequency of the CN or CO stretching mode, bond length, and dipole moment of this bond with varying applied electric fields are shown. The transition polarizability and the difference polarizability were also calculated by DFT for comparison to the experimental data on nitriles and carbonyls. The DFT calculations suggest that the sign of the transition polarizability is negative and this result in turn has an effect on the experimental data analysis since the sign of the transition polarizability is not determined by experiment.
TL;DR: In this article, the deflection and deceleration of neutral hydrogen molecules in the presence of an inhomogeneous electric field is demonstrated, where the molecules are laser-excited in a molecular beam to selected Rydberg-Stark states in the field of an electric dipole for a fixed period, and their trajectories are monitored using ion imaging and time-of-flight measurement.
TL;DR: In this article, the influence of ion dynamics on the profiles of the Hα and Hβ lines of the hydrogen Balmer series was investigated and it was shown that the difference between the electron density values from both the Hβ and Hα lines is about 3%.
Abstract: In this work we have performed experimental research into the influence of ion dynamics on the profiles of the Hα and Hβ lines of the hydrogen Balmer series. In order to understand this influence the electron density of a microwave plasma column at atmospheric pressure is measured from the Stark broadening of both lines. However, in this case Kepple–Griem's theory is not used, as usual, but a new computational model based on the μ-ion model that includes the effect of the ion dynamics on the profiles. The results obtained show that the difference between the electron density values from both the Hα and Hβ lines is about 3%. So, it is possible to use the Hα line for the diagnosis of the electron density in those cases in which it is not possible to use the Hβ line; for example, when the Hβ line is not intense enough.
TL;DR: In this paper, the authors analyzed the spectroscopic properties of Yb 3+ ion in a new oxide single crystal belonging to the potassium bismuth molybdate family with the following concentrations: K 5 Bi 1-x -Yb x (Mo 0 4 ) 4 (x = 0.005, 0.05,0.15).
TL;DR: In this article, a detailed analysis of the energy levels of Dy3+ and DyAlO3 + 4f9 is presented for the 15 lowest-energy 2S+1LJ multiplet manifolds.
Abstract: A detailed crystal-field splitting analysis is reported for the energy levels of Dy3+(4f9) in crystals of YAlO3 and DyAlO3 orthoaluminates. Experimental energy (Stark) levels for the 15 lowest-energy 2S+1LJ multiplet manifolds of Dy3+ are reported and supplemented with values found in the literature. A parameterized Hamiltonian, including Coulombic, spin-orbit, configuration interaction, and crystal-field terms in Cs symmetry, was diagonalized for the 6HJ, 6FJ, 4FJ, 4IJ, and 4GJ states. Initial sets of crystal-field parameters were determined from lattice-sum calculations and the three-parameter theory. Considerable J-mixing is found for states having nearly the same energy such as the manifolds 6F11/2, 6H9/2, and 6F9/2, 6H7/2. Even states that are well separated from each other in energy show sufficient J mixing to explain the polarized absorption and Zeeman effects that involve transitions from the nearly pure (less than 0.2% J mixing) ground state, 6H15/2 to excited states such as 6F5/2 and 6F3/2. The rms for 70 calculated-to-experimental Stark levels for Dy3+ in YAlO3 is 10 cm−1; the rms for 43 calculated-to-experimental levels for Dy3+ in DyAlO3 is 8 cm−1.
TL;DR: In this article, the authors analyzed the time-resolved photoluminescence (TRPL) data of c-In0.1Ga0.9N/GaN MQWs and showed that the spontaneous emission is due to the radiative recombination of excitons localized in disordered quantum nanostructures forming extended and localized states.
Abstract: Recombination dynamics of localized excitons in strained cubic (c-)InxGa1−xN/GaN multiple quantum wells (MQWs) grown on 3C–SiC (001) were summarized in terms of well thickness L, InN molar fraction x, and temperature T. Photoluminescence (PL) peak energy of c-In0.1Ga0.9N/GaN MQWs showed a moderate blueshift as L decreased, and the low-temperature PL lifetime did not change remarkably by changing L. These results proved that the quantum-confined Stark effect due either to spontaneous or piezoelectric polarization was inactive in cubic polytypes. Consequently, time-resolved PL (TRPL) data of c-InGaN MQWs reflect the intrinsic exciton dynamics. The TRPL signal showed stretched exponential decay and spectral redshift with time after excitation up to 300 K. The results are fingerprints that the spontaneous emission is due to the radiative recombination of excitons localized in disordered quantum nanostructures forming extended and localized states. Effective localization depth increased with the increase in x,...
TL;DR: In this article, it was shown that strongly polarized quasi-one-dimensional very high-n (potassium) Rydberg atoms can be produced by photoexcitation of selected Stark states in the presence of a weak dc field.
Abstract: We demonstrate that strongly polarized quasi-one-dimensional very-high-n (potassium) Rydberg atoms can be produced by photoexcitation of selected Stark states in the presence of a weak dc field. Calculations show that, for m=0 states, significant photoexcitation occurs only in the vicinity of the Stark-shifted s, p, and d levels, and that those states located near the Stark-shifted d level have sizable polarizations. These predictions are confirmed by experiment. The degree of polarization of the product states is analyzed by studying differences in their ionization characteristics when subject to short pulsed electric fields applied parallel and antiparallel to the dc field.
TL;DR: In this article, potential-dependent surface-enhanced Raman scattering spectra of the nitrile stretching mode were acquired from a series of monolayers composed of alkanethiols (HS(CH2)xCH3, where 6 ≤ x ≤ 10) and mercaptododecanenitrile (HS 2)11CN).
Abstract: Potential-dependent surface-enhanced Raman scattering (SERS) spectra of the nitrile stretching mode were acquired from a series of monolayers composed of alkanethiols (HS(CH2)xCH3, where 6 ≤ x ≤ 10) and mercaptododecanenitrile (HS(CH2)11CN). These spectra were used to investigate the diffuse double layer at a silver electrode interface modified with mixed self-assembled monolayers (SAMs). The alkanethiol species acts to dilute the nitrile-terminated thiol to isolate the nitrile reporter group within the diffuse double-layer region. Nitrile groups co-immobilized with shorter diluent alkanethiol chains are placed more deeply into the diffuse double layer (relative to the methyl terminus of the surrounding alkanethiol). Interfacial electric fields, measured using observed Stark tuning rates of the nitrile stretching frequency, were examined as a function of SAM composition to map the structure of the diffuse double-layer region versus distance from the SAM/solution interface. The trends in the experimental d...
TL;DR: In this article, a single trapped, laser-cooled ion of {sup 171}Yb{sup +} has been measured to be f{sub Yb{Sup +}}=642 121 496 771.26(23) kHz using a femtosecond laser frequency comb generator.
Abstract: The {sup 2}S{sub 1/2}(F=0){yields}{sup 2}F{sub 7/2}(F=3,m{sub F}=0) transition at 467 nm in a single trapped, laser-cooled ion of {sup 171}Yb{sup +} has been measured to be f{sub Yb{sup +}}=642 121 496 771.26(23) kHz using a femtosecond laser frequency comb generator. The measurement is limited by measurement statistics and by the ac Stark shift, both related to the 4.5 kHz linewidth of the probe laser at the time. The systematic shifts of the transition, including ac Stark, second-order Zeeman, quadrupole, and blackbody shifts, have been evaluated.