Variable Range Hopping Conduction in Semiconductor Nanocrystal Solids
Abstract
The temperature and electrical field dependent conductivity of n-type CdSe nanocrystal thin films is investigated. In the low electrical field regime, the conductivity follows σ∼exp([-(T*/T)1/2] in the temperature range 10<T<120 K. At high electrical field, the conductivity is strongly field dependent. At 4K, the conductance increases by 8orders of magnitude over one decade of bias. At a very high field, conductivity is temperature independent with σ∼exp([-(E*/E)1/2]. The complete behavior is very well described by variable range hopping with a Coulomb gap.
- Publication:
-
Physical Review Letters
- Pub Date:
- May 2004
- DOI:
- 10.1103/PhysRevLett.92.216802
- arXiv:
- arXiv:cond-mat/0403597
- Bibcode:
- 2004PhRvL..92u6802Y
- Keywords:
-
- 73.22.-f;
- 05.60.Cd;
- 73.50.Fq;
- 73.63.Kv;
- Electronic structure of nanoscale materials: clusters nanoparticles nanotubes and nanocrystals;
- Classical transport;
- High-field and nonlinear effects;
- Quantum dots;
- Materials Science
- E-Print:
- Submitted to Physical Review Letters on Dec. 22, 2003