Search

Your search keyword '"Baldwin, K. W."' showing total 668 results
Start Over Author "Baldwin, K. W."
668 results on '"Baldwin, K. W."'

207. Resistivity anisotropy of quantum Hall stripe phases

Author

Sammon, M., primary, Fu, X., additional, Huang, Yi, additional, Zudov, M. A., additional, Shklovskii, B. I., additional, Gardner, G. C., additional, Watson, J. D., additional, Manfra, M. J., additional, Baldwin, K. W., additional, Pfeiffer, L. N., additional, and West, K. W., additional

Published
2019
Full Text
View/download PDF

211. Geometric resonance of four-flux composite fermions

Author

Hossain, Md. Shafayat, primary, Ma, Meng K., additional, Mueed, M. A., additional, Kamburov, D., additional, Pfeiffer, L. N., additional, West, K. W., additional, Baldwin, K. W., additional, Winkler, R., additional, and Shayegan, M., additional

Published
2019
Full Text
View/download PDF

213. Ballistic Electron Optics

Author

Spector, J., primary, Weiner, J. S., additional, Stormer, H. L., additional, Baldwin, K. W., additional, Pfeiffer, L. N., additional, and West, K. W., additional

Published
1992
Full Text
View/download PDF

214. Full momentum- and energy-resolved spectral function of a 2D electronic system

Author

Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology. Department of Physics, Jang, Joonho, Yoo, Heun Mo, Ashoori, Raymond, Pfeiffer, L. N., West, K. W., Baldwin, K. W., Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology. Department of Physics, Jang, Joonho, Yoo, Heun Mo, Ashoori, Raymond, Pfeiffer, L. N., West, K. W., and Baldwin, K. W.

Abstract

The single-particle spectral function measures the density of electronic states in a material as a function of both momentum and energy, providing central insights into strongly correlated electron phenomena. Here we demonstrate a high-resolution method for measuring the full momentum- and energy-resolved electronic spectral function of a two-dimensional (2D) electronic system embedded in a semiconductor. The technique remains operational in the presence of large externally applied magnetic fields and functions even for electronic systems with zero electrical conductivity or with zero electron density. Using the technique on a prototypical 2D system, a GaAs quantum well, we uncover signatures of many-body effects involving electron-phonon interactions, plasmons, polarons, and a phonon analog of the vacuum Rabi splitting in atomic systems.

Published
2019

224. Realization of a Valley Superlattice

Author

Mueed, M. A., primary, Hossain, Md. Shafayat, additional, Jo, I., additional, Pfeiffer, L. N., additional, West, K. W., additional, Baldwin, K. W., additional, and Shayegan, M., additional

Published
2018
Full Text
View/download PDF

238. Bloch ferromagnetism of composite fermions

Author

Hossain, Md Shafayat, Zhao, Tongzhou, Pu, Songyang, Mueed, M. A., Ma, M. K., Villegas Rosales, K. A., Chung, Y. J., Pfeiffer, L. N., West, K. W., Baldwin, K. W., Jain, J. K., and Shayegan, M.

Abstract

In 1929, Felix Bloch suggested that the paramagnetic Fermi sea of electrons should make a spontaneous transition to a fully magnetized state at very low densities, because the exchange energy gained by aligning the spins exceeds the enhancement in the kinetic energy1. However, experimental realizations of this effect have been hard to implement. Here, we report the observation of an abrupt, interaction-driven transition to full magnetization, highly reminiscent of Bloch ferromagnetism. Our platform utilizes the two-dimensional Fermi sea of composite fermions near half-filling of the lowest Landau level. We measure the Fermi wavevector—which directly provides the spin polarization—and observe a sudden transition from a partially spin-polarized to a fully spin-polarized ground state as we lower the density of the composite fermions. Our theoretical calculations that take Landau level mixing into account provide a semi-quantitative account of this phenomenon.

Published
2021
Full Text
View/download PDF

240. Impact of the modulation doping layer on the ��=5/2 anisotropy

Author

Shi, X., Pan, W., Baldwin, K. W., West, K. W., Pfeiffer, L. N., and Tsui, D. C.

Subjects
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), FOS: Physical sciences, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect
Abstract

We have carried out a systematic study of the tilted magnetic field induced anisotropy at the Landau level filling factor ��=5/2 in a series of high quality GaAs quantum wells, where the setback distance (d) between the modulation doping layer and the GaAs quantum well is varied from 33 to 164 nm. We have observed that in the sample of the smallest d electronic transport is anisotropic when the in-plane magnetic field (B_{ip}) is parallel to the [1-10] crystallographic direction, but remains more or less isotropic when B_{ip} // [110]. In contrast, in the sample of largest d, electronic transport is anisotropic in both crystallographic directions. Our results clearly show that the modulation doping layer plays an important role in the tilted field induced ��=5/2 anisotropy., Phys. Rev. B 91, 125308 (2015)

Published
2015
Full Text
View/download PDF

241. Composite Fermion Geometric Resonance Near �� = 1/2 Fractional Quantum Hall State

Author

Mueed, M. A., Kamburov, D., Hasdemir, S., Shayegan, M., Pfeiffer, L. N., West, K. W., and Baldwin, K. W.

Subjects
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), FOS: Physical sciences
Abstract

We observe geometric resonance features of composite fermions on the flanks of the even denominator �� = 1/2 fractional quantum Hall state in high-mobility two-dimensional electron and hole systems confined to wide GaAs quantum wells and subjected to a weak, strain-induced, unidirectional periodic potential modulation. The features provide a measure of how close to �� = 1/2 the system stays single-component and supports a composite fermion Fermi sea before transitioning into a �� = 1/2 fractional quantum Hall state, presumably the two-component ��331 state.

Published
2015
Full Text
View/download PDF

244. Signatures of an annular Fermi sea

Author

Jo, Insun, primary, Liu, Yang, additional, Pfeiffer, L. N., additional, West, K. W., additional, Baldwin, K. W., additional, Shayegan, M., additional, and Winkler, R., additional

Published
2017
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results