There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

Spintronics, or spin electronics, involves the study of active control and manipulation of spin degrees of freedom in solid-state systems. This article reviews the current status of this subject, including both recent advances and well-established results. The primary focus is on the basic physical principles underlying the generation of carrier spin polarization, spin dynamics, and spin-polarized transport in semiconductors and metals. Spin transport differs from charge transport in that spin is a nonconserved quantity in solids due to spin-orbit and hyperfine coupling. The authors discuss in detail spin decoherence mechanisms in metals and semiconductors. Various theories of spin injection and spin-polarized transport are applied to hybrid structures relevant to spin-based devices and fundamental studies of materials properties. Experimental work is reviewed with the emphasis on projected applications, in which external electric and magnetic fields and illumination by light will be used to control spin and charge dynamics to create new functionalities not feasible or ineffective with conventional electronics.

/pdf/spintronics-fundamentals-and-applications-2dx38n6phu.pdf

Spintronics: Fundamentals and applications

Conventional optical components rely on gradual phase shifts accumulated during light propagation to shape light beams. New degrees of freedom are attained by introducing abrupt phase changes over the scale of the wavelength. A two-dimensional array of optical resonators with spatially varying phase response and subwavelength separation can imprint such phase discontinuities on propagating light as it traverses the interface between two media. Anomalous reflection and refraction phenomena are observed in this regime in optically thin arrays of metallic antennas on silicon with a linear phase variation along the interface, which are in excellent agreement with generalized laws derived from Fermat’s principle. Phase discontinuities provide great flexibility in the design of light beams, as illustrated by the generation of optical vortices through use of planar designer metallic interfaces.

http://www.zenogaburro.it/papers/LightPropagation.pdf

Light Propagation with Phase Discontinuities: Generalized Laws of Reflection and Refraction

We performed a novel phase-sensitive microwave reflection experiment which directly probes the dynamics of the Josephson plasma resonance in both the linear and the nonlinear regime. When the junction was driven below the plasma frequency into the nonlinear regime, we observed for the first time the transition between two different dynamical states predicted for nonlinear systems. In our experiment, this transition appears as an abrupt change in the reflected signal phase at a critical excitation power. This controlled dynamical switching can form the basis of a sensitive amplifier, in particular, for the readout of superconducting qubits.

Direct observation of dynamical bifurcation between two driven oscillation states of a Josephson junction.

Detailed measurements of the voltage, temperature, and frequency dependence of the nonequilibriumcurrent ﬂuctuations for a diffusive mesoscopic conductor are reported. The data conﬁrm predictionsthat a mesoscopic conductor shorter than the electron-electron inelastic length will display shotnoise. Furthermore, the low temperatures (100 mK) and high frequencies (1–20 GHz) used for themeasurements allow tests in the high-frequency regime (i.e.,

http://www.burkelab.com/wp-content/uploads/p3370_1.pdf

Frequency Dependence of Shot Noise in a Diffusive Mesoscopic Conductor

Communication that relies on quantum carriers, like single photons, can achieve a level of privacy unattainable by classical communication methods. In a new experiment, single microwave photons are used as carriers of quantum information in a manner robust to loss.

https://hal-mines-paristech.archives-ouvertes.fr/hal-01403587/document

Robust Concurrent Remote Entanglement Between Two Superconducting Qubits

/pdf/circuit-qed-superconducting-qubits-coupled-to-microwave-4u3qj4u31a.pdf

Circuit QED: Superconducting Qubits Coupled to Microwave Photons

The ability to transfer quantum information from a memory to a flying qubit is important for building quantum networks. The very fast release of a multiphoton state in a microwave cavity memory into propagating modes is demonstrated.

Robert Schoelkopf

Papers

Direct observation of dynamical bifurcation between two driven oscillation states of a Josephson junction.

Frequency Dependence of Shot Noise in a Diffusive Mesoscopic Conductor

Robust Concurrent Remote Entanglement Between Two Superconducting Qubits

Circuit QED: Superconducting Qubits Coupled to Microwave Photons

Controlled release of multiphoton quantum states from a microwave cavity memory