Zobrazeno 1 - 10
of 72
pro vyhledávání: '"Kumar, Nardeep"'
Exciton binding energy and excited states in monolayers of tungsten diselenide (WSe2) are investigated using the combined linear absorption and two-photon photoluminescence excitation spectroscopy. The exciton binding energy is determined to be 0.37e
Externí odkaz:
http://arxiv.org/abs/1406.3095
Publikováno v:
Phys. Rev. B 89, 125427 (2014)
We investigate the excitonic dynamics in MoSe2 monolayer and bulk samples by femtosecond transient absorption microscopy. Excitons are resonantly injected by a 750-nm and 100-fs laser pulse, and are detected by a probe pulse tuned in the range of 790
Externí odkaz:
http://arxiv.org/abs/1311.1079
Publikováno v:
J. Appl. Phys. 113, 133702 (2013)
We report a transient absorption microscopy study of charge carrier dynamics in bulk MoS2 crystals at room temperature. Charge carriers are injected by interband absorption of a 555-nm pulse, and probed by measuring differential reflection of a time-
Externí odkaz:
http://arxiv.org/abs/1303.0749
Autor:
Kumar, Nardeep, Najmaei, Sina, Cui, Qiannan, Ceballos, Frank, Ajayan, Pulickel M., Lou, Jun, Zhao, Hui
Publikováno v:
Phys. Rev. B 87, 161403(R) (2013)
We show that the lack of inversion symmetry in monolayer MoS2 allows strong optical second harmonic generation. Second harmonic of an 810-nm pulse is generated in a mechanically exfoliated monolayer, with a nonlinear susceptibility on the order of 1E
Externí odkaz:
http://arxiv.org/abs/1302.3935
Autor:
Kumar, Nardeep, Kumar, Jatinder, Gerstenkorn, Chris, Wang, Rui, Chiu, Hsin-Ying, Smirl, Arthur L., Zhao, Hui
Publikováno v:
Phys. Rev. B 87, 121406(R) (2013)
We observe optical third harmonic generation from graphene and few-layer graphite flakes produced by exfoliation. The emission scales with the cube of the intensity of the incident near-infrared femtosecond pulses and has a wavelength that is one-thi
Externí odkaz:
http://arxiv.org/abs/1301.1042
Publikováno v:
Phys. Rev. B 86, 045406 (2012)
Atomically-thin molybdenum disulfide is emerging as a new nanomaterial with potential applications in the fields of electronic and photonics. Charge carrier dynamics plays an essential role in determining its electronic and optical properties. We rep
Externí odkaz:
http://arxiv.org/abs/1206.6055
Femtosecond optical pump-probe technique is used to study charge carrier dynamics in few-layer MoS2 samples fabricated by mechanical exfoliation. An ultrafast pump pulse excites carriers and differential reflection of a probe pulse tuned to an excito
Externí odkaz:
http://arxiv.org/abs/1110.6643
Autor:
Kumar, Nardeep, Ruzicka, Brian A., Butch, N. P., Syers, P., Kirshenbaum, K., Paglione, J., Zhao, Hui
Publikováno v:
Phys. Rev. B 83, 235306 (2011)
Carrier and phonon dynamics in Bi2Se3 crystals are studied by a spatially resolved ultrafast pump-probe technique. Pronounced oscillations in differential reflection are observed with two distinct frequencies, and are attributed to coherent optical a
Externí odkaz:
http://arxiv.org/abs/1104.0349
Publikováno v:
J. Appl. Phys.109, 084322 (2011)
The energy relaxation of carriers in reduced graphene oxide thin films is studied using optical pump-probe spectroscopy with two probes of different colors. We measure the time difference between peaks of the carrier density at each probing energy by
Externí odkaz:
http://arxiv.org/abs/1103.0728
Autor:
Lysenko, Sergiy, Rúa, Armando, Kumar, Nardeep, Lu, Junqiang, Yan, Jia-An, Theran, Larry, Echeverria, Karla, Ramos, Leonardo, Goenaga, Gabriel, Hernández-Rivera, Samuel P., Fernández, Félix E.
Publikováno v:
Journal of Applied Physics; 1/14/2021, Vol. 129 Issue 2, p1-12, 12p
