Graphene-Semiconductor Quantum Well with Asymmetric Energy Gaps
- 1 Department of Physics, Southern University and A & M College, Baton Rouge, USA
- 2 Department of Physics, Southern University and A & M College, Baton Rouge, USA
- 3 Department of Physics, Southern University and A & M College, Baton Rouge, USA
- 4 Department of Physics, Xiamen University, Xiamen, China
- 5 Institute of Mechanics, Chinese Academy of Sciences, Beijing, China
- 6 Department of Physics, University of Houston, Houston, USA
Abstract
Semiconductor solar cell (PV cell) has been widely used for generating solar electricity. However, the high cost and severe pollution limits its application. Recently the discovery of graphene may open a door to fabricate a novel solar cell with lower cost and more environmentally friendly. Our proposed solar cell device consists of a graphene strip and two semiconductor strips with different energy gaps attached to the two edges of the graphene strip on a flat plane. This structure is a two-dimensional quantum well. The energy bands of graphene can be described by a two-dimensional Dirac equation centered on hexagonal corners (Dirac points) of the honeycomb lattice Brillouin zone. The 2 D Dirac equation has been solved numerically in this paper. The results indicate that the graphene quantum well possesses very dense quantum energy states which imply that quantum well of this type can absorb sun light with more different fre quencies. If we use graphene quantum well to fabricate the photo voltaic cell, the efficiency of converting solar energy to electricity will be enhanced.
- L.-P. An, T.-B. Wang, and N.-H. Liu, “Inter-Well Coupling and Resonant Tunneling Modes of Multiple Graphene Quantum Wells”, Communications in Theoretical Physics, Vol. 56, No. 2, 2011, pp. 367-372. doi:10.1088/0253-6102/56/2/29
- J. M. Pereira Jr, V. Mlinar and F. M. Peeters, “Confined States and Direction-Dependent Transmission in Graphene Quantum Wells,” Physical Review B, Vol. 74, No. 4, 2006, pp. 1-5.
- P. R. Wallace, “The Band Theory of Graphite,” Physical Review, Vol. 71, No. 9, 1947, pp. 622-634. doi:10.1103/PhysRev.71.622
- M. Wilson, Physics Today, 2006, p. 21.
- G. W. Semenoff, “Condensed-Matter Simulation of a Three-Dimensional Anomaly,” Physical Review Letters, Vol. 53, No. 26, 1984, pp. 2449-2452. doi:10.1103/PhysRevLett.53.2449c
- I. A. Luk’yanchuk and Y. Kopelevich, “Phase Analysis of Quantum Oscillations in Graphite,” Physical Review Letters, Vol. 93, No. 16, 2004, pp. 166402-166406. doi:10.1103/PhysRevLett.93.166402
- L. A. ponomarenko, F. Schedin, M. I. Katsnelson, et al., Science, Vol. 320, 2008, p. 356.
- T. Ando, J. Phys. Soc. Jpn. Vol. 74, No. , 2005, pp. 777. doi:10.1143/JPSJ.74.777
- P. V. Ratnikov and A. P. Silin, “Quantum Well Based on Graphene and Narrow-Gap Semiconductors,” Bulletin of the Lebedev Physics Institute, Vol. 36, No. 2, 2009, pp. 34-43. doi:10.3103/S106833560902002X
- K. S. Novoselov, A. K. Geim, S. V. Morozov, et al., Nature, Vol. 438, 2005, p. 197.
- Y. Zhang, Y.-W. Tan, H. L. Stormer and P. Kim, Nature, Vol. 438, 2005, p. 201. doi:10.1038/nature04235
- L. Brey and H. A. Fertig, “Electronic States of Graphene Nanoribbons Studied with the Dirac Equation,” Physical Review B, Vol. 73, No. 23, 2006, pp. 235411-235416. doi:10.1103/PhysRevB.73.235411
- L. Brey and H. A. Fertig, “Elementary Electronic Excitations in Graphene Nanoribbons,” Physical Review B, Vol. 75, No. 12, 2007, pp. 125434-125440. doi:10.1103/PhysRevB.75.125434
- Y.-W. Son, M. L. Cohen and S. G. Louie, “Energy Gaps in Graphene Nanoribbons,” Physical Review Letters, Vol. 97, No. 21, 2006, pp. 216803-216807. doi:10.1103/PhysRevLett.97.216803
- E. Mccann and V. I. Fal’ko, “Symmetry of Boundary Conditions of the Dirac Equation for Electrons in Carbon Nanotubes,” Journal of Physics: Condensed Matter, Vol. 16, No. 13, 2004, p. 2371. doi:10.1088/0953-8984/16/13/016