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DOE OSTI · 3021227

Light-induced electron pairing in a bilayer structure

Wan, Qiaochu [University of Pittsburgh, PA (United States)] (ORCID:0000000348779722)·Vaz, Daniel [University of Pittsburgh, PA (United States)] (ORCID:0000000320957590)·Xiang, Li [Florida State University, Tallahassee, FL (United States)] (ORCID:0000000215650271)·Ramavath, Anshul [University of Pittsburgh, PA (United States)] (ORCID:000900073341636X)·Vargo, Brandon [University of Pittsburgh, PA (United States)] (ORCID:000900003020271X)·Ye, Juntong [University of Pittsburgh, PA (United States)] (ORCID:0009000237552282)·Beaumariage, Jonathan [University of Pittsburgh, PA (United States)] (ORCID:0009000475002999)·Watanabe, Kenji [National Institute for Materials Science, Tsukuba (Japan)] (ORCID:0000000337018119)·Taniguchi, Takashi [National Institute for Materials Science, Tsukuba (Japan)] (ORCID:0000000214673105)·Sun, Zheng [East China Normal University, Shanghai (China)] (ORCID:0000000252092563)·Smirnov, Dmitry [Florida State University, Tallahassee, FL (United States)] (ORCID:0000000163583221)·Youngblood, Nathan [University of Pittsburgh, PA (United States)] (ORCID:0000000325529376)·Bondarev, Igor V. [North Carolina Central University, Durham, NC (United States)] (ORCID:000000030739210X)·Snoke, David [University of Pittsburgh, PA (United States)] (ORCID:0000000182076524)
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Abstract

We demonstrate the existence of doubly charged exciton states in strongly screened bilayers of transition metal dichalcogenide layers. These complexes are important because they are preformed electron pairs that can, in principle, undergo Bose–Einstein condensation, in which case they would also form a new type of superconductor, consisting of stable bosons with net charge. Our measurements include 1) continuous control of the doping density with both positive and negative carriers, showing the expected population dependencies on the free carrier density, and 2) measurement of the dependence on magnetic field, showing that this new bound state is a spin triplet. These results imply that it is promising to look for superconductivity in this system.

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Wan, Qiaochu [University of Pittsburgh, PA (United States)] (ORCID:0000000348779722), Vaz, Daniel [University of Pittsburgh, PA (United States)] (ORCID:0000000320957590), Xiang, Li [Florida State University, Tallahassee, FL (United States)] (ORCID:0000000215650271), Ramavath, Anshul [University of Pittsburgh, PA (United States)] (ORCID:000900073341636X), Vargo, Brandon [University of Pittsburgh, PA (United States)] (ORCID:000900003020271X), Ye, Juntong [University of Pittsburgh, PA (United States)] (ORCID:0009000237552282), Beaumariage, Jonathan [University of Pittsburgh, PA (United States)] (ORCID:0009000475002999), Watanabe, Kenji [National Institute for Materials Science, Tsukuba (Japan)] (ORCID:0000000337018119), Taniguchi, Takashi [National Institute for Materials Science, Tsukuba (Japan)] (ORCID:0000000214673105), Sun, Zheng [East China Normal University, Shanghai (China)] (ORCID:0000000252092563), Smirnov, Dmitry [Florida State University, Tallahassee, FL (United States)] (ORCID:0000000163583221), Youngblood, Nathan [University of Pittsburgh, PA (United States)] (ORCID:0000000325529376), Bondarev, Igor V. [North Carolina Central University, Durham, NC (United States)] (ORCID:000000030739210X), Snoke, David [University of Pittsburgh, PA (United States)] (ORCID:0000000182076524). 2026-01-21. Light-induced electron pairing in a bilayer structure. https://doi.org/10.1088/1361-6633%2Fae2ba1

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