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

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

We review the field of cavity optomechanics, which explores the interaction between electromagnetic radiation and nano- or micromechanical motion This review covers the basics of optical cavities and mechanical resonators, their mutual optomechanical interaction mediated by the radiation pressure force, the large variety of experimental systems which exhibit this interaction, optical measurements of mechanical motion, dynamical backaction amplification and cooling, nonlinear dynamics, multimode optomechanics, and proposals for future cavity quantum optomechanics experiments In addition, we describe the perspectives for fundamental quantum physics and for possible applications of optomechanical devices

Cavity Optomechanics

It is now shown that coupled optical microcavities bear all the hallmarks of parity–time symmetry; that is, the system’s dynamics are unchanged by both time-reversal and mirror transformations. The resonant nature of microcavities results in unusual effects not seen in previous photonic analogues of parity–time-symmetric systems: for example, light travelling in one direction is resonantly enhanced but there are no resonance peaks going the other way.

Parity–time-symmetric whispering-gallery microcavities

In recent years, notions drawn from non-Hermitian physics and parity–time (PT) symmetry have attracted considerable attention. In particular, the realization that the interplay between gain and loss can lead to entirely new and unexpected features has initiated an intense research effort to explore non-Hermitian systems both theoretically and experimentally. Here we review recent progress in this emerging field, and provide an outlook to future directions and developments. This Review Article outlines the exploration of the interplay between parity–time symmetry and non-Hermitian physics in optics, plasmonics and optomechanics.

Non-Hermitian physics and PT symmetry

We demonstrate detection and sizing of single nanoparticles down to 30 nm by monitoring the mode splitting induced by a nanoparticle in an ultra-high quality factor (UHQ) microtoroid. Theory and methods are discussed.

Detection and sizing of single nanoparticles by mode splitting in an optical microresonator

Nature provides a set of solutions for photonic structures that are finely tuned, organically diverse and optically efficient. Exquisite knowledge of structure-property relationships in proteins aids in the design of materials with desired properties for building devices with novel functionalities, which are difficult to achieve or previously unattainable. Here we report whispering-gallery-mode (WGM) microresonators fabricated entirely from semi-crystalline structural proteins (i.e., squid ring teeth, SRT, from Loligo vulgaris and its recombinant) with quality factors as high as 105. We first demonstrate versatility of protein-based devices via facile doping, engaging secondary structures. Then we investigate thermo-refractivity and find that it increases with beta-sheet crystallinity which can be altered by methanol exposure and is higher in the selected recombinant SRT protein than its native counterpart. We present a set of photonic devices fabricated from SRT proteins such as add-drop filters and fibe...

Structural Protein-based Flexible Whispering Gallery Mode Resonators

Optimization of germanium-based perovskite solar cells by SCAPS simulation

With extremely low material absorption and exceptional surface smoothness, silica-based optical resonators can achieve extremely high cavity quality (Q) factors. However, the intrinsic material limitations of silica (e.g., lack of second order nonlinearity) may limit the potential applications of silica-based high Q resonators. Here we report some results in utilizing layer-by-layer self-assembly to functionalize silica microspheres with nonlinear and plasmonic nanomaterials while maintaining Q factors as high as 107. We compare experimentally measured Q factors with theoretical estimates, and find good agreement.

High quality factor silica microspheres functionalized with self-assembled nanomaterials

We have demonstrated the detection of a 12MHz ultrasound wave using a microtoroidal whispering gallery mode optical resonator, encapsulated in a low-refractive-index polymer with its coupling tapered-fiber. The sensitivity of our device is 35 mV/KPa.

Lan Yang

Papers

Detection and sizing of single nanoparticles by mode splitting in an optical microresonator

Structural Protein-based Flexible Whispering Gallery Mode Resonators

Optimization of germanium-based perovskite solar cells by SCAPS simulation

High quality factor silica microspheres functionalized with self-assembled nanomaterials

Ultrasound sensing using a fiber coupled silica microtoroid resonator encapsulated in a polymer