journal article·2022-11-22Open access

Thickness- and Twist-Angle-Dependent Interlayer Excitons in Metal Monochalcogenide Heterostructures

Wenkai Zheng, Li Xiang, Felipe A. de Quesada, Mathias Augustin, Zhengguang Lu, Matthew Wilson, Aditya Sood, Fengcheng Wu, Dmitry Shcherbakov, Shahriar Memaran, Ryan E. Baumbach, Gregory T. McCandless, Julia Y. Chan, Song Liu, James H. Edgar, Chun Ning Lau, Chun Hung Lui, Elton J. G. Santos, Aaron Lindenberg, Dmitry Smirnov, Luis Balicas

ACS Nano· Volume 16· Issue 11

Abstract

Interlayer excitons, or bound electron–hole pairs whose constituent quasiparticles are located in distinct stacked semiconducting layers, are being intensively studied in heterobilayers of two-dimensional semiconductors. They owe their existence to an intrinsic type-II band alignment between both layers that convert these into p–n junctions. Here, we unveil a pronounced interlayer exciton (IX) in heterobilayers of metal monochalcogenides, namely, γ-InSe on ε-GaSe, whose pronounced emission is adjustable just by varying their thicknesses given their number of layers dependent direct band gaps. Time-dependent photoluminescense spectroscopy unveils considerably longer interlayer exciton lifetimes with respect to intralayer ones, thus confirming their nature. The linear Stark effect yields a bound electron–hole pair whose separation d is just (3.6 ± 0.1) Å with d being very close to dSe = 3.4 Å which is the calculated interfacial Se separation. The envelope of IX is twist-angle-dependent and describable by superimposed emissions that are nearly equally spaced in energy, as if quantized due to localization induced by the small moiré periodicity. These heterostacks are characterized by extremely flat interfacial valence bands making them prime candidates for the observation of magnetism or other correlated electronic phases upon carrier doping.
Source: openalex_inverted_index · Quality: baseline

Research context

OpenAlex topics: 2D Materials and Applications · Chalcogenide Semiconductor Thin Films · Iron-based superconductors research

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

National High Magnetic Field Laboratory, Tallahassee, Florida32310, United States

Department of Physics, Florida State University, Tallahassee, Florida32306, United States

Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California94025, United States

Department of Materials Science and Engineering, Stanford University, Stanford, California94305, United States

Institute for Condensed Matter Physics and Complex Systems, School of Physics and Astronomy, The University of Edinburgh, EdinburghEH9 3FD, United Kingdom

Higgs Centre for Theoretical Physics, The University of Edinburgh, EdinburghEH9 3FD, United Kingdom

Department of Physics and Astronomy, University of California, Riverside, California92521, United States

School of Physics and Technology, Wuhan University, Wuhan, 430072China

Department of Physics, The Ohio State University, Columbus, Ohio43210, United States

Department of Chemistry and Biochemistry, Baylor University, Waco, Texas76798, United States

Tim Taylor Department of Chemical Engineering, Kansas State University, Manhattan, Kansas66506, United States

Donostia International Physics Centre, 20018Donostia-San Sebastian, Spain

Funding

Engineering and Physical Sciences Research Council · Welch Foundation · Basic Energy Sciences · Ministerio de Ciencia e Innovación · University Of Edinburgh · Office of Naval Research Global · American Chemical Society Petroleum Research Fund · Division of Civil, Mechanical and Manufacturing Innovation · Division of Materials Research

References (71)

Show source-provided references
1. 10.1103/PhysRevLett.86.560810.1103/PhysRevLett.86.5608 ↗
2. 10.1038/ncomms555510.1038/ncomms5555 ↗
3. 10.1088/1361-6633/aa50e310.1088/1361-6633/aa50e3 ↗
4. 10.1126/science.aah475810.1126/science.aah4758 ↗
5. 10.1038/nphys181210.1038/nphys1812 ↗
6. 10.1021/nl300983n10.1021/nl300983n ↗
7. 10.1038/nature1090310.1038/nature10903 ↗
8. 10.1103/PhysRevLett.103.08740310.1103/PhysRevLett.103.087403 ↗
9. 10.1021/nl900605b10.1021/nl900605b ↗
10. 10.1103/PhysRevLett.96.22740210.1103/PhysRevLett.96.227402 ↗
11. 10.1038/417047a10.1038/417047a ↗
12. 10.1103/PhysRevLett.92.11740510.1103/PhysRevLett.92.117405 ↗
13. 10.1038/nnano.2014.16710.1038/nnano.2014.167 ↗
14. 10.1038/ncomms724210.1038/ncomms7242 ↗
15. 10.1038/s41586-018-0357-y10.1038/s41586-018-0357-y ↗
16. 10.1103/PhysRevB.41.856410.1103/PhysRevB.41.8564 ↗
17. 10.1038/s41566-021-00908-610.1038/s41566-021-00908-6 ↗
18. 10.1038/s41563-020-0687-710.1038/s41563-020-0687-7 ↗
19. 10.1126/sciadv.170169610.1126/sciadv.1701696 ↗
20. 10.1103/PhysRevLett.118.14740110.1103/PhysRevLett.118.147401 ↗
21. 10.1038/s41586-019-0976-y10.1038/s41586-019-0976-y ↗
22. 10.1038/s41586-019-0975-z10.1038/s41586-019-0975-z ↗
23. 10.1038/s41586-019-0957-110.1038/s41586-019-0957-1 ↗
24. 10.1038/s41586-019-0986-910.1038/s41586-019-0986-9 ↗
25. 10.1038/s41563-020-0708-610.1038/s41563-020-0708-6 ↗
26. 10.1021/acs.nanolett.7b0512510.1021/acs.nanolett.7b05125 ↗
27. 10.1126/sciadv.160145910.1126/sciadv.1601459 ↗
28. 10.1038/nature1218610.1038/nature12186 ↗
29. 10.1038/nature2615410.1038/nature26154 ↗
30. 10.1038/nature2616010.1038/nature26160 ↗
31. 10.1126/science.aaw378010.1126/science.aaw3780 ↗
32. 10.1038/s41586-020-2970-910.1038/s41586-020-2970-9 ↗
33. 10.1073/pnas.200034711710.1073/pnas.2000347117 ↗
34. 10.1021/acsnano.7b0064010.1021/acsnano.7b00640 ↗
35. 10.1088/2053-1583/aadfc310.1088/2053-1583/aadfc3 ↗
36. 10.1038/nnano.2016.24210.1038/nnano.2016.242 ↗
37. 10.1021/acsami.0c0963510.1021/acsami.0c09635 ↗
38. 10.1103/PhysRevLett.105.13680510.1103/PhysRevLett.105.136805 ↗
39. 10.1063/1.491413410.1063/1.4914134 ↗
40. 10.1021/acsanm.0c0228010.1021/acsanm.0c02280 ↗
41. 10.1088/1361-6528/aa749e10.1088/1361-6528/aa749e ↗
42. 10.1021/acs.nanolett.6b0327610.1021/acs.nanolett.6b03276 ↗
43. 10.1126/sciadv.abe289210.1126/sciadv.abe2892 ↗
44. 10.1126/science.aat698110.1126/science.aat6981 ↗
45. 10.1126/science.aac782010.1126/science.aac7820 ↗
46. 10.1021/acs.nanolett.7b0130410.1021/acs.nanolett.7b01304 ↗
47. 10.1126/sciadv.aax014510.1126/sciadv.aax0145 ↗
48. 10.1126/sciadv.aba886610.1126/sciadv.aba8866 ↗
49. 10.1126/science.aaw419410.1126/science.aaw4194 ↗
50. 10.1103/PhysRevLett.126.04740110.1103/PhysRevLett.126.047401 ↗
51. 10.1126/science.abm851110.1126/science.abm8511 ↗
52. 10.1038/s41565-021-01068-y10.1038/s41565-021-01068-y ↗
53. 10.1038/s41565-020-00783-210.1038/s41565-020-00783-2 ↗
54. 10.1038/s41565-020-0750-110.1038/s41565-020-0750-1 ↗
55. 10.1103/PhysRevA.55.460910.1103/PhysRevA.55.4609 ↗
56. 10.1038/s41566-018-0325-y10.1038/s41566-018-0325-y ↗
57. 10.1038/s41563-020-0730-810.1038/s41563-020-0730-8 ↗
58. 10.1038/s41563-021-00923-610.1038/s41563-021-00923-6 ↗
59. 10.1126/science.aba977810.1126/science.aba9778 ↗
60. 10.1103/PhysRevB.55.698110.1103/PhysRevB.55.6981 ↗
61. 10.1038/ncomms1064310.1038/ncomms10643 ↗
62. 10.1038/s41586-020-2092-410.1038/s41586-020-2092-4 ↗
63. 10.1038/s41563-019-0601-310.1038/s41563-019-0601-3 ↗
64. 10.1021/acs.cgd.7b0087110.1021/acs.cgd.7b00871 ↗
65. 10.1107/S160057671402298510.1107/S1600576714022985 ↗
66. 10.1107/S205327331402637010.1107/S2053273314026370 ↗
67. 10.1107/S205322961402421810.1107/S2053229614024218 ↗
68. 10.1021/nn500228r10.1021/nn500228r ↗
69. 10.1103/PhysRevB.54.1116910.1103/PhysRevB.54.11169 ↗
70. 10.1103/PhysRevB.59.175810.1103/PhysRevB.59.1758 ↗
71. 10.1063/1.220459710.1063/1.2204597 ↗