Article

# Capacitance of gated GaAs/AlxGa1-xAs heterostructures subject to in-plane magnetic fields.

Physical review. B, Condensed matter (Impact Factor: 3.77). 05/1995; 51(15):10181-10184. DOI: 10.1103/PhysRevB.51.10181

Source: PubMed

- [Show abstract] [Hide abstract]

**ABSTRACT:**We present a theoretical study of magnetocapacitance in a graphene monolayer at finite temperature taking into account the effects of disorder. The density of states (DOS) and magnetocapacitance found for graphene are compared to those found in standard two dimensional electron gas (2DEG) systems. The magnetic oscillations in DOS and magnetocapacitance are found to be enhanced and much more robust with respect to temperature damping in monolayer graphene in comparison with a 2DEG. Furthermore, we find that there is a $\pi$ phase shift between magnetic oscillations in the two systems which can be attributed to Dirac electrons in graphene acquiring a Berry's phase as they traverse a closed path in a magnetic field.08/2008; - [Show abstract] [Hide abstract]

**ABSTRACT:**In this paper we present calculations on the density of states (DOS) and the magnetocapacitance of the 2DEG in a MODFET under two-dimensional (2D) weak periodic modulation in the presence of a perpendicular magnetic field. Adopting a Gaussian broadening of magnetic-field-dependent width, we present explicit and simple expressions for the DOS, valid for the relevant weak magnetic fields and modulation strengths. As the modulation strength in both directions increase, beating patterns of the magnetocapacitance oscillations are observed in the low-magnetic-field range (Weiss-oscillations regime) which are absent in the 1D weak modulation case.Microelectronics Journal. 01/2007; - [Show abstract] [Hide abstract]

**ABSTRACT:**The temperature dependence of the compressibility of two-dimensional electron systems (2DESs) in GaAs/AlGaAs heterostructures in the quantum Hall effect regime have been studied both experimentally and theoretically. The compressibility was determined using the capacitance spectroscopy technique and the measurements of a low-frequency electric field penetrating through the 2DES. The measured temperature dependences of the 2DES compressibility are quantitatively described using a model taking into account inhomogeneity of the electron density at a finite temperature. Changes in the chemical potential of the 2DES in the vicinity of even filling factors determined from the capacitive and transport measurements are mutually consistent and agree with the results of finite-temperature calculations.Journal of Experimental and Theoretical Physics 05/2004; 98(6):1222-1230. · 0.92 Impact Factor

Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.