Cooling of mechanical resonators is currently a popular topic in many fields of physics including ultra-high precision measurements1, detection of gravitational waves, and the study of the transition between classical and quantum behaviour of a mechanical system. Here we report the observation of self-cooling of a micromirror by radiation pressure inside a high-finesse optical cavity. In essence, changes in intensity in a detuned cavity, as caused by the thermal vibration of the mirror, provide the mechanism for entropy flow from the mirror's oscillatory motion to the low-entropy cavity field. The crucial coupling between radiation and mechanical motion was made possible by producing free-standing micromirrors of low mass (m ≈ 400 ng), high reflectance (more than 99.6%) and high mechanical quality (Q ≈ 10,000). We observe cooling of the mechanical oscillator by a factor of more than 30; that is, from room temperature to below 10 K. In addition to purely photothermal effects we identify radiation pressure as a relevant mechanism responsible for the cooling. In contrast with earlier experiments, our technique does not need any active feedback. We expect that improvements of our method will permit cooling ratios beyond 1,000 and will thus possibly enable cooling all the way down to the quantum mechanical ground state of the micromirror.

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Self-cooling of a micromirror by radiation pressure

The invention relates to an optical device. The optical device comprises a waveguide core and a nanocomposite material optically coupled to the waveguide core. The nanocomposite material includes a plurality of quantum dots. The nanocomposite material has a nonlinear index of refraction γ that is at least 10 −9 cm 2 /W when irradiated with an activation light having a wavelength λ between approximately 3×10 −5 cm and 2×10 −4 cm.

Optical devices with engineered nonlinear nanocomposite materials

There is provided a first reservoir containing a liquid solution including a molecule to be characterized and a second reservoir for containing a liquid solution including a molecule that has been characterized. A solid state support structure is provided including an aperture having a molecular entrance providing a fluidic connection to the first reservoir and a molecular exit providing a fluidic connection to the second reservoir. First and second electron transport probes are each disposed on the support structure with a surface abutting a perimeter of the aperture. At least one of the probes comprises a fullerene structure, e.g., a carbon nanotube. A voltage source is connected between the probes to apply a voltage bias across the aperture. An electrical current monitor is connected between the probes for monitoring changes in electron transport between the probes corresponding to translocation of a molecule through the aperture.

Molecular characterization with carbon nanotube control

The claimed invention provides for new sample preparation methods enabling direct sequencing of PCR products using pyrophosphate sequencing techniques. The PCR products may be specific regions of a genome. The techniques provided in this disclosure allows for SNP (single nucleotide polymorphism) detection, classification, and assessment of individual allelic polymorphisms in one individual or a population of individuals. The results may be used for diagnostic and treatment of patients as well as assessment of viral and bacterial population identification.

Methods for determining sequence variants using ultra-deep sequencing

An electro-optical switch (10) implemented in coupled photonic crystal waveguides (12, 14) is disclosed. The switch (10) is proposed and analyzed using both a finite-difference time-domain ('FDTD') method and a plane wave expansion ('PWM') method. The switch (10) may be implemented in a square lattice (18) of silicon posts in air, as well as in a hexagonal lattice (38) of air holes in a silicon slab. Switching occurs due to a change in the conductance in the coupling region between the photonic crystal waveguides (12, 14), which modulates the coupling coefficient and eventually causes switching. Conductance may be induced electrically by carrier injection or optically by electron-hole pair generation. The electro-optical switch (10) has low insertion loss and optical crosstalk in both the cross and bar switching states.

Electro-optical switching using coupled photonic crystal waveguides

The present invention provides an apparatus and method for identifying and sequencing a biopolymer translocating a nanopore. The apparatus of the present invention provides a first electrode, a second electrode and a potential means for applying a bias ramping potential across the electrodes to produce resonant tunneling of current carriers between the two electrodes. As the bias potential is ramped across the electrodes the increase in tunneling current occurs as the carrier energy sequentially matches the conduction band energies of the translocating biopolymer. This technique allows for real-time identification and sequencing of a biopolymer as the band energy spectra of the individual portions of the bipolymer are recorded, differentiated and identified. A method for identifying the biopolymer is also disclosed.

Apparatus and method for biopolymer identification during translocation through a nanopore

The invention provides a method for controlled fabrication of a solid state structural feature. In the method, a solid state structure is provided and the structure is exposed to an ion beam, under fabrication process conditions for producing the structural feature. A physical detection species is directed toward a designated structure location, and the rate at which the detection species proceeds from the designated structure location is measured. Detection species rate measurements are fit to a mathematical model, and the fabrication process conditions are controlled, based on the fitted detection species rate measurements, to fabricate the structural feature.

High-precision feedback control for ion sculpting of solid state features

The present invention provides an apparatus and method for controlling the movement of a biopolymer translocating a nanopore. The invention provides a first electrode, a second electrode adjacent to the first electrode, a third electrode adjacent to the second electrode and a fourth electrode adjacent to the third electrode. The first electrode is in electrical connection with the third electrode to define a first set of electrodes and the second electrode is in electrical connection with the fourth electrode to define a second set of electrodes. A DC voltage and radio frequency voltage is applied to the first set of electrodes while an opposite DC voltage and phase shifted radio frequency voltage is applied to the second set of electrodes to produce an electric field between the first set of electrodes and the second set of electrodes. The electric field is used to control the movement of a biopolymer translocating a nanopore. A method for controlling the movement of a biopolymer is also disclosed.

Apparatus and method for control of biopolymer translocation through a nanopore

In this paper, we examine thermal noise and radiation-pressure effects in MEMS tunable Fabry-Perot etalons. We show that thermal noise causes a jitter in the center wavelength in very high finesse etalons. In turn, the jitter causes an effective increase in the time-averaged filter bandwidth. Radiation pressure is of little consequence in conventional Fabry-Perot etalons, but it can give rise to nonlinearities and hysteresis in the tuning response of high-finesse MEMS filters. We develop models of noise and optical nonlinearities and compare the models with a series of measurements on commercial tunable high-finesse MEMS Fabry-Perot etalons.

Thermal noise and radiation pressure in MEMS Fabry-Perot tunable filters and lasers

Two-dimensional photonic crystal slab apparatus and a method for fabricating two-dimensional photonic crystal slab apparatus. A two-dimensional photonic crystal slab apparatus has a photonic crystal slab containing a two-dimensional periodic lattice, and upper and lower cladding layers for the photonic crystal slab, the upper and lower cladding layers each having a metallic cladding layer. The metallic cladding layers permit achieving substantially perfect light transmission through a waveguide in the slab, even when the waveguide is strongly bent. The fabrication method includes forming a two-dimensional photonic crystal slab from a dielectric slab supported on a substrate by, for example, an etch process.

Curt A. Flory

Papers

Apparatus and method for biopolymer identification during translocation through a nanopore

High-precision feedback control for ion sculpting of solid state features

Apparatus and method for control of biopolymer translocation through a nanopore

Thermal noise and radiation pressure in MEMS Fabry-Perot tunable filters and lasers

Two-dimensional photonic crystal slab waveguide