Ultrahigh Hall mobility and suppressed backward scattering in layered semiconductor Bi2O2Se

Abstract

We report on an ultrahigh Hall mobility exceeding 40 000 cm2/V s and a very long traditional scattering time in a trivial layered semiconductor Bi2O2Se. Shubnikov-de Haas (SdH) oscillations were observed in both the unsaturated longitudinal linear magnetoresistance Rxx and the transverse Hall resistance Rxy. The amplitude ΔRxy of SdH oscillations was phase-shifted approximately 180° with respect to ΔRxx, indicating the strong suppression of electron backward scattering. This was further proved by the evidence of transport lifetime that is 10 times longer than the quantum lifetime. Our results show that the suppressed backward scattering in nontrivial Dirac semimetals can also occur in the trivial semiconductor Bi2O2Se.

Surface electronic structure of bismuth oxychalcogenides

“…Additionally, Bi 2 O 2 Se may be used as an optical switch for the exploitation of compact and high-performance midinfrared pulsed laser sources [56]. In Reference [57] was found a strong reduction in amplitude of the universal conductance fluctuations and showed that this result agrees with the assumed strong spin-orbit interaction in the Bi 2 O 2 Se nanoplate. The strong spin-orbit interaction in Bi 2 O 2 Se nanoplates has also been confirmed through magnetotransport measurements [55].…”

Infrared and Raman spectra of Bi2O2X and Bi2OX2 (X = S, Se, and Te) studied from first principles calculations

“…12 Recently, it was found that the low temperature (about 2 K) Hall mobility can reach more than 2.0 Â 10 4 cm 2 s À1 V À1 in Bi 2 O 2 Se thin lm [13][14][15] and 4.0 Â 10 4 cm 2 s À1 V À1 in Bi 2 O 2 Se single crystal. 16 Very recently, we have observed a superior Hall mobility of 2.2 Â 10 5 cm 2 s À1 V À1 at 2 K in a high quality Bi 2 O 2 Se single crystal. 17 The high mobility in Bi 2 O 2 Se is possibly due to the self-modulation doping, i.e.…”

“…[8][9][10][11] Second, Bi 2 O 2 Se has an ultrahigh electron mobility. [12][13][14][15][16][17] An earlier work in 2012 found that the room temperature Hall mobility of Bi 2 O 2 Se single crystal was on the order of 300 cm 2 s À1 V À1 . 12 Recently, it was found that the low temperature (about 2 K) Hall mobility can reach more than 2.0 Â 10 4 cm 2 s À1 V À1 in Bi 2 O 2 Se thin lm [13][14][15] and 4.0 Â 10 4 cm 2 s À1 V À1 in Bi 2 O 2 Se single crystal.…”

“…A longitudinal MR of about 600% (at 15 Tesla and 2 K) and 9000% (at 9 Tesla and 2 K) in Bi 2 O 2 Se single crystals was observed in two recent experiments. 16,17 Third, due to its high mobility and suitable band gap (about 0.8 eV), Bi 2 O 2 Se was used in optoelectronic devices and infrared (IR) photo-detectors. [20][21][22] Bi 2 O 2 Te has the same crystal structure as that of Bi 2 O 2 Se, but it is much less studied.…”

“…Only a few works about the Raman spectra of Bi 2 O 2 Se and Bi 2 O 2 Te have been reported until now. 14,16,37,38 For this reason, we have systematically calculated the phonon, irreducible representations, Raman and IR spectra, vibrational eigenvectors of optical phonons, and polarized Raman congurations of six materials: Bi 2 O 2 X and Bi 2 OX 2 . We mainly present the results of Bi 2 O 2 Se and Bi 2 O 2 Te since they can be compared with other works.…”