Peak-to-valley ratio of small resonant-tunneling diodes with various barrier-thickness asymmetries

Applied Physics Letters

Volumn 68, Issue 6, 1996, Pages 838-840

  Schmidt, T ^a   Tewordt, M ^a   Haug, R J ^a   Klitzing, K V ^a   Schonherr B ^a   Grambow, P ^a   Forster A ^b   Luth H ^b  

^a MAX PLANCK INSTITUT FÜR FESTKÖRPERFORSCHUNG   (Germany)

^b FORSCHUNGSZENTRUM JÜLICH   (Germany)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0039868969     PISSN: 00036951     EISSN: None     Source Type: Journal    
DOI: 10.1063/1.116550     Document Type: Article

References (10)

1. For a review see Physics of Quantum Electron Devices, edited by F. Capasso (Springer, New York, 1990).
2. See e.g. H. C. Liu and T. C. L. G. Sollner, Semicond. Semimet. 41, 359 (1994).
3. M. A. Reed, J. N. Randall, R. J. Aggarwal, R. J. Matyi, T. M. Moore, and A. E. Wetsel, Phys. Rev. Lett. 60, 535 (1988).
4. M. Tewordt, V. J. Law, M. J. Kelly, R. Newbury, M. Pepper, D. C. Peacock, J. E. F. Frost, D. A. Ritchie, and G. A. C. Jones, J. Phys. Condens. Matt. 2, 8969 (1990).
5. B. Su, V. J. Goldman, and J. E. Cunningham, Phys. Rev. B 46, 7644 (1992).
6. T. Schmidt, M. Tewordt, R. H. Blick, R. J. Haug, D. Pfannkuche, K. v. Klitzing, A. Förster, and H. Lüth, Phys. Rev. B 51, 5570 (1995).
7. A. Zaslavsky, V. J. Goldman, D. C. Tsui, and J. E. Cunningham, Appl. Phys. Lett. 53, 1228 (1988).
8. An increasing emitter-barrier thickness reduces the peak voltage because a growing part of the applied bias drops between the emitter contact and the quantum well, i.e. the subband in the quantum well is shifted to lower energy at a given bias. This is however a minor effect in our case since the variation of the emitter-barrier thickness is small compared to the length of the undoped device region across which the applied bias drops.
9. V. J. Goldman, D. C. Tsui, and J. E. Cunningham, Phys. Rev. Lett. 58, 1256 (1987).
10. Hopping through possible mid-band-gap surface defects at the Fermi level would also decrease the peak-to-valley ratio. Such a parallel current path would be especially relevant for positive bias because of the lower overall current density compared to negative bias [see Figs. 2 (a) and (b)]. However, the presence of significant defect-related currents is not likely as we observe no Ohmic contribution in the current valleys in Fig. 2 (b).