Author(s): Lai, JM (Lai, Jia-Min); Sun, YJ (Sun, Yu-Jia); Tan, QH (Tan, Qing-Hai); Tan, PH (Tan, Ping-Heng); Zhang, J (Zhang, Jun)

Source: NANO LETTERS DOI: 10.1021/acs.nanolett.2c02240 Early Access Date: AUG 2022

Abstract: Laser cooling atoms and molecules to ultralow temperatures has produced plenty of opportunities in fundamental physics, precision metrology, and quantum science. Although theoretically proposed over 40 years, the laser cooling of certain lattice vibrations (i.e., phonon) remains a challenge owing to the complexity of solid structures. Here, we demonstrate Raman cooling of a longitudinal optical phonon in two-dimensional semiconductor WS2 by red-detuning excitation at the sideband of the exciton (bound electron-hole pair). Strong coupling between the phonon and exciton and appreciable optomechanical coupling rates provide access to cooling high-frequency phonons that are robust against thermal decoherence even at room temperature. Our experiment opens possibilities of laser cooling and control of individual optical phonon and, eventually, possible cooling of matter in van der Waals semiconductor.

Accession Number: WOS:000848118900001

PubMed ID: 35993841

Author Identifiers:

Author        Web of Science ResearcherID        ORCID Number

Zhang, Jun                  0000-0002-9831-6796

TAN, Ping-Heng         D-1137-2009         0000-0001-6575-1516

ISSN: 1530-6984

eISSN: 1530-6992

Full Text: https://pubs.acs.org/doi/10.1021/acs.nanolett.2c02240