JILA X317

Designing sensors with tensioned silicon nitride micromechanical resonators

When
-

Abstract: Mechanical resonators based on stressed silicon nitride have both exemplary optical and mechanical properties. Through targeted shaping of the resonator geometry, the dissipative properties of these resonators can be enhanced, yielding micromechanical devices that maintain coherence for up to billions of oscillation periods.

Single molecule ligand binding kinetics and environmental adaptations in lysine riboswitches

When
-

Abstract: Riboswitches are important RNA structures in bacteria and some eukaryotes that can bind a ligand to toggle between conformations that allow or terminate transcription, translation, or splicing. We study folding kinetics and thermodynamics in the B. subtilis and T. maritima lysine riboswitches via single molecule TIRF microscopy. We show that riboswitch folding is exothermic with a large entropic cost, which we attribute to increased binding pocket rigidity upon lysine binding.

Brownian Motion of a Resonator Linked to a Spatially Varying Thermal Bath

When
-

We are excited to announce the first CU Phonon Club seminar of the semester. Please join us for a great talk, interesting discussion, and FREE FOOD. We are pleased to feature Dr. Ravid Shaniv from Prof. Regal's group who will be presenting their recent work. Also, we are planning on hosting two more talks this semester. Feel free to pass this email along to any others who may be interested. We hope to see you on Wednesday!

Heralded Spectroscopy - a new probe for nanocrystal multiexciton photophysics

When
-

Abstract:

Emitters of quantum light are at the core of quantum optic science and a key resource for emerging classical and quantum technologies. Yet, to date, the tools available to study multiple-photon quantum light sources, specifically temporally and spectrally in parallel, have been limited. A prominent example is multiply-excited semiconductor quantum dots - an intriguing system that features rich physics and technological potential but lacks direct observation techniques. 

Emergence of fluctuating hydrodynamics in chaotic quantum systems

When
-

Out-of-equilibrium dynamics of isolated quantum many-body systems is generally intractable. In chaotic quantum systems, however, local observables rapidly relax to their equilibrium values. Hence, simple translationally-invariant initial states are expected to quickly reach thermal equilibrium for local expectation values. The equilibration of fluctuations on the other hand goes beyond standard thermalization and is expected to happen on much longer timescales, since their approach to equilibrium is limited by the hydrodynamic build-up of large-scale fluctuations.