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Generating coherent phonon waves in narrow-band materials: a twisted bilayer graphene phaser

Esin, Iliya and Esterlis, Ilya and Demler, Eugene and Refael, Gil (2022) Generating coherent phonon waves in narrow-band materials: a twisted bilayer graphene phaser. . (Unpublished)

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Twisted bilayer graphene (TBG) exhibits extremely low Fermi velocities for electrons, with the speed of sound surpassing the Fermi velocity. This regime enables the use of TBG for amplifying vibrational waves of the lattice through stimulated emission, following the same principles of operation of free-electron lasers. Our work proposes a lasing mechanism relying on the slow-electron bands to produce a coherent beam of acoustic phonons. We propose a device based on undulated electrons in TBG, which we dub the phaser. The device generates phonon beams in a terahertz (THz) frequency range, which can then be used to produce THz electromagnetic radiation. The ability to generate coherent phonons in solids breaks new ground in controlling quantum memories, probing quantum states, realizing non-equilibrium phases of matter, and designing new types of THz optical devices.

Item Type:Report or Paper (Discussion Paper)
Related URLs:
URLURL TypeDescription Paper
Esin, Iliya0000-0003-2959-0617
Esterlis, Ilya0000-0003-4775-9105
Demler, Eugene0000-0002-2499-632X
Additional Information:Attribution 4.0 International (CC BY 4.0). We thank Kenneth Burch, Jerome Faist, Mohammad Hafezi, Atac Imamoglu, Cyprian Lewandowski, Marios Michael, Leo Radzihovsky, and Christopher Yang for valuable discussions. G. Refael and I. Esin are grateful for support from the Simons Foundation and the Institute of Quantum Information and Matter, as well as support from the NSF DMR grant number 1839271. E. Demler and I. Esterlis acknowledge support from the ARO grant “Control of Many-Body States Using Strong Coherent Light-Matter Coupling in Terahertz Cavities”. This work is supported by ARO MURI Grant No. W911NF-16-1-0361, and was performed in part at Aspen Center for Physics, which is supported by National Science Foundation grant PHY-1607611.
Group:Institute for Quantum Information and Matter
Funding AgencyGrant Number
Simons FoundationUNSPECIFIED
Institute for Quantum Information and Matter (IQIM)UNSPECIFIED
Army Research Office (ARO)W911NF-16-1-0361
Record Number:CaltechAUTHORS:20220816-183030641
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:116310
Deposited By: George Porter
Deposited On:16 Aug 2022 21:42
Last Modified:16 Aug 2022 21:42

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