All posts by cmeriles_1ry5wvws
05-20: Daniela and Pablo’s Science Advances paper makes it to the news! Congratulations!
See, for example, EurekaAlert, ScienceDaily, or CUNY/CUNY-SUM.
04-20: Gabriel’s paper selected for OSA Spotlight!
Spotlight Summary by Igor Aharonovich
Room-temperature single photon emitters in cubic boron nitride nanocrystals
Boron nitride has recently emerged as the platform of choice to study light-matter interaction at the nanoscale. So far, efforts have been dedicated to study hexagonal boron nitride (hBN)—as it has been shown to host bright quantum emitters. In this paper, López-Morales and colleagues report for the first time that also defects in cubic boron nitride (cBN), a cubic polymorph of BN, can act as quantum light sources. Like its hexagonal counterpart, cBN also possesses a large bandgap, which means it can host a plethora of optically active defects. The study shows the promising properties of these defects—including narrow linewidths and fast lifetime. The results are intriguing as the cubic symmetry of cBN is likely to host defects with symmetries resembling the nitrogen-vacancy center in diamond, and hence possess promising spin properties that can be harnessed for scalable quantum photonic applications.
Find more information here.
03-20: Gabriel’s paper on color centers in cubic boron nitride chosen for the cover of OMEX. Congrats!
Color centers in wide bandgap semiconductors are attracting broad attention for use as platforms for quantum technologies relying on room-temperature single-photon emission (SPE), and for nanoscale metrology applications building on the centers’ response to electric and magnetic fields. Here, we demonstrate room-temperature SPE from defects in cubic boron nitride (cBN) nanocrystals, which we unambiguously assign to the cubic phase using spectrally resolved Raman imaging. These isolated spots show photoluminescence (PL) spectra with zero-phonon lines (ZPLs) within the visible region (496–700 nm) when subject to sub-bandgap laser excitation. Second-order autocorrelation of the emitted photons reveals antibunching with g2(0) ∼ 0.2, and a decay constant of 2.75 ns that is further confirmed through fluorescence lifetime measurements. The results presented herein prove the existence of optically addressable isolated quantum emitters originating from defects in cBN, making this material an interesting platform for opto-electronic devices and quantum applications.
01-20: Daniela and Pablo’s paper on spin thermalization accepted in Science Advances. Congratulations!
12-19: Farewell to Hari. Best of luck in Minnesota!
11-19: Mingxing’s baby is born! Congratulations to the new dad!
10-19: Prof. Rodolfo Acosta from the Universidad Nacional de Cordoba joins us for a two-week stay
10-19: Mishkatul Bhattacharya from the Rochester Institute of Technology tells us about how to engineer a phonon laser
Optical Tweezer Phonon Laser
Abstract: We are in the middle of a revolution in phononics, where it seems useful and possible to control phonons as we have photons in the last few decades. In this talk
I will describe our theoretical proposal and its experimental demonstration regarding
a phonon laser made of the center-of-mass oscillations of a nanoparticle trapped in an
optical tweezer. I will report on threshold behavior, coherence, subthermal number
squeezing, time dynamics, phase space characterization, injection locking, Q switching
and the role of stimulated emission in our single mode phonon laser. Based on this discussion
I will conclude that our device provides a pathway for engineering a coherent source of
phonons on the mesoscale that can be applied to both fundamental problems in quantum
mechanics as well as tasks of precision metrology.
09-19: Sakib presents his poster at the ORCA meeting.
