Revealing the biexciton and trion-exciton complexes in BN encapsulated WSe2

Abstract

Strong Coulomb interactions in single-layer transition metal dichalcogenides (TMDs) result in the emergence of strongly bound excitons, trions, and biexcitons. These excitonic complexes possess the valley degree of freedom, which can be exploited for quantum optoelectronics. However, in contrast to the good understanding of the exciton and trion properties, the binding energy of the biexciton remains elusive, with theoretical calculations and experimental studies reporting discrepant results. In this work, we resolve the conflict by employing low-temperature photoluminescence spectroscopy to identify the biexciton state in BN-encapsulated single-layer WSe 2 . The biexciton state only exists in charge-neutral WSe 2 , which is realized through the control of efficient electrostatic gating. In the lightly electron-doped WSe 2 , one free electron binds to a biexciton and forms the trion–exciton complex. Improved understanding of the biexciton and trion–exciton complexes paves the way for exploiting the many-body physics in TMDs for novel optoelectronics applications.

Full text

Its licence does not allow us to show the full text. Read it at PubMed Central:

References 53

1. 1.

   Splendiani A, et al. Emerging photoluminescence in monolayer MoS2. Nano Lett. 2010;10:1271-1275.

   Not in our library10.1021/nl903868w

2. 2.

   Mak KF, Lee C, Hone J, Shan J, Heinz TF. Atomically thin MoS2: a new direct-gap semiconductor. Phys. Rev. Lett. 2010;105:136805.

   Not in our library10.1103/physrevlett.105.136805

3. 3.

   Jones AM, et al. Optical generation of excitonic valley coherence in monolayer WSe2. Nat. Nanotechnol. 2013;8:634-638.

   Not in our library10.1038/nnano.2013.151

4. 4.

   Li Y, et al. Valley splitting and polarization by the zeeman effect in monolayer MoSe2. Phys. Rev. Lett. 2014;113:1-5.

   Not in our library10.1103/physrevlett.113.266804

5. 5.

   Macneill D, et al. Breaking of valley degeneracy by magnetic field in monolayer MoSe2. Phys. Rev. Lett. 2015;114:1-5.

   Not in our library10.1103/physrevlett.114.037401

6. 6.

   Aivazian G, et al. Magnetic control of valley pseudospin in monolayer WSe2. Nat. Phys. 2015;11:148-152.

   Not in our library10.1038/nphys3201

7. 7.

   Srivastava A, et al. Valley Zeeman effect in elementary optical excitations of monolayer WSe2. Nat. Phys. 2015;11:141-147.

   Not in our library10.1038/nphys3203

8. 8.

   Mak KF, He K, Shan J, Heinz TF. Control of valley polarization in monolayer MoS2 by optical helicity. Nat. Nanotechnol. 2012;7:494-498.

   Not in our library10.1038/nnano.2012.96

9. 9.

   Gong Z, et al. Magnetoelectric effects and valley-controlled spin quantum gates in transition metal dichalcogenide bilayers. Nat. Commun. 2013;4:1-6.

   Not in our library10.1038/ncomms3053

10. 10.

    Cao T, et al. Valley-selective circular dichroism of monolayer molybdenum disulphide. Nat. Commun. 2012;3:885-887.

    Not in our library10.1038/ncomms1894

11. 11.

    Ye Z, Sun D, Heinz TF. Optical manipulation of valley pseudospin. Nat. Phys. 2017;13:26-29.

    Not in our library10.1038/nphys3891

12. 12.
    Trion fine structure and coupled spin–valley dynamics in monolayer tungsten disulfide · 2016

    No notice
13. 13.

    Xu X, Yao W, Xiao D, Heinz TF. Spin and pseudospins in layered transition metal dichalcogenides. Nat. Phys. 2014;10:343-350.

    Not in our library10.1038/nphys2942

14. 14.

    Mak KF, Shan J. Photonics and optoelectronics of 2D semiconductor transition metal dichalcogenides. Nat. Photonics. 2016;10:216-226.

    Not in our library10.1038/nphoton.2015.282

15. 15.

    Mak KF, et al. Tightly bound trions in monolayer MoS2. Nat. Mater. 2012;12:207-211.

    Not in our library10.1038/nmat3505

16. 16.

    Ross JS, et al. Electrical control of neutral and charged excitons in a monolayer semiconductor. Nat. Commun. 2013;4:1-8.

    Not in our library10.1038/ncomms2498

17. 17.

    Courtade E, et al. Charged excitons in monolayer WSe2: experiment and theory. Phys. Rev. B. 2017;96:1-12.

    Not in our library10.1103/physrevb.96.085302

18. 18.

    Qiu DY, Da Jornada FH, Louie SG. Optical spectrum of MoS2: Many-body effects and diversity of exciton states. Phys. Rev. Lett. 2013;111:1-5.

    Not in our library10.1103/physrevlett.111.216805

19. 19.

    Ugeda MM, et al. Giant bandgap renormalization and excitonic effects in a monolayer transition metal dichalcogenide semiconductor. Nat. Mater. 2014;13:1091-1095.

    Not in our library10.1038/nmat4061

20. 20.

    You Y, et al. Observation of biexcitons in monolayer WSe2. Nat. Phys. 2015;11:477-481.

    Not in our library10.1038/nphys3324

21. 21.
    Ror2 signaling regulates Golgi structure and transport through IFT20 for tumor invasiveness · 2017

    No notice
22. 22.

    Plechinger G, et al. Identification of excitons, trions and biexcitons in single-layer WS2. Phys. Status Solidi Rapid Res. Lett. 2015;9:457-461.

    Not in our library10.1002/pssr.201510224

23. 23.

    Qin Q, et al. Excited state biexcitons in atomically thin MoSe2. ACS Nano. 2017;11:7468-7475.

    Not in our library10.1021/acsnano.7b04786

24. 24.

    Shang J, et al. Observation of excitonic fine structure in a 2D transition-metal dichalcogenide semiconductor. ACS Nano. 2015;9:647-655.

    Not in our library10.1021/nn5059908

25. 25.

    Nagler, P. et al. Zeeman splitting and inverted polarization of biexciton emission in monolayer WS2. Phys. Rev. Lett. 121, 057402 (2018).

    Not in our library10.1103/physrevlett.121.057402

26. 26.

    Lee YH, Kim J. Biexciton emission from edges and grain boundaries of triangular WS2 monolayers. ACS Nano. 2016;10:2399-2405.

    Not in our library10.1021/acsnano.5b07214

27. 27.

    Paradisanos I., Germanis S., Pelekanos N. T., Fotakis C., Kymakis E., Kioseoglou G., Stratakis E. Room temperature observation of biexcitons in exfoliated WS2 monolayers. Applied Physics Letters. 2017;110(19):193102.

    Not in our library10.1063/1.4983285

28. 28.

    Steinhoff, A. et al. Biexciton fine structure in monolayer transition metal dichalcogenides. Preprint at https//arxiv.org/abs/1801.04225 (2018).

    Not in our library

29. 29.
    In situ click chemistry generation of cyclooxygenase-2 inhibitors · 2017

    No notice
30. 30.

    Fang S, et al. Ab initio tight-binding Hamiltonian for transition metal dichalcogenides. Phys. Rev. B. 2015;92:1-15.

    Not in our library

31. 31.

    Rybkovskiy DV, Gerber IC, Durnev MV. Atomically inspired k·p approach and valley Zeeman effect in transition metal dichalcogenide monolayers. Phys. Rev. B. 2016;155406:1-9.

    Not in our library

32. 32.

    Kidd DW, Zhang DK, Varga K. Binding energies and structures of two-dimensional excitonic complexes in transition metal dichalcogenides. Phys. Rev. B. 2016;93:1-10.

    Not in our library10.1103/physrevb.93.125423

33. 33.

    Kylänpää I, Komsa HP. Binding energies of exciton complexes in transition metal dichalcogenide monolayers and effect of dielectric environment. Phys. Rev. B. 2015;92:1-6.

    Not in our library10.1103/physrevb.92.205418

34. 34.

    Mayers MZ, Berkelbach TC, Hybertsen MS, Reichman DR. Binding energies and spatial structures of small carrier complexes in monolayer transition-metal dichalcogenides via diffusion Monte Carlo. Phys. Rev. B. 2015;92:1-5.

    Not in our library10.1103/physrevb.92.161404

35. 35.

    Wang L, et al. One-dimensional electrical contact to a two-dimensional material. Science. 2013;342:614-617.

    Not in our library10.1126/science.1244358

36. 36.

    Zhang Z, et al. Robust epitaxial growth of two-dimensional heterostructures, multiheterostructures, and superlattices. Science. 2017;6814:1-9.

    Not in our library10.1126/science.aan6814

37. 37.

    Cadiz F, et al. Excitonic linewidth approaching the homogeneous limit in MoS2-based van der Waals heterostructures. Phys. Rev. X. 2017;7:1-12.

    Not in our library

38. 38.

    Yu H, Liu G, Gong P, Xu X, Yao W. Dirac cones and Dirac saddle points of bright excitons in monolayer transition metal dichalcogenides. Nat. Commun. 2014;5:1-7.

    Not in our library10.1038/ncomms4876

39. 39.

    Jones AM, et al. Excitonic luminescence upconversion in a two-dimensional semiconductor. Nat. Phys. 2016;12:1-11.

    Not in our library10.1038/nphys3604

40. 40.

    Zhang XX, et al. Magnetic brightening and control of dark excitons in monolayer WSe2. Nat. Nanotechnol. 2017;12:883-888.

    Not in our library10.1038/nnano.2017.105

Cited by papers we hold 2

• Nanocavity-induced trion emission from atomically thin WSe2 · 2022
  Not checked
• Interlayer exciton formation, relaxation, and transport in TMD van der Waals heterostructures · 2021
  No notice

Reads

A person counts once a day per paper. We keep no cookie and no address: a reader is a hash that changes every day. Any month under five reads shows no number.