Related papers: Hole-flux Composite Fermion Commensurability Oscil…
Electronic stripe/nematic phases are fascinating strongly-correlated states characterized by spontaneous rotational symmetry breaking. In the quantum Hall regime, such phases typically emerge at half-filled, high-orbital-index ($N\geq2$)…
Composite fermions (CFs), exotic particles formed by pairing an even number of flux quanta to each electron, provide a fascinating description of phenomena exhibited by interacting two-dimensional electrons at high magnetic fields. At and…
We report on a theoretical study of the commensurability oscillations in a quasi-two-dimensional electron gas modulated by a unidirectional periodic potential and subjected to tilted magnetic fields with a strong in-plane component. As a…
Two-dimensional electron or hole systems in semiconductors offer the unique opportunity to investigate the physics of strongly interacting fermions. We have measured the 1/f resistance noise of two-dimensional hole systems in high mobility…
We present a composite fermion theory of tunneling into the edge of a compressible quantum Hall system. The tunneling conductance is non-ohmic, due to slow relaxation of electromagnetic and Chern-Simons field disturbances caused by the…
In the framework of a recently developed model of interacting composite fermions restricted to a single level, we calculate the activation gaps of a second generation of spin-polarized composite fermions. These composite particles consist…
The $\nu=2/5$ state is spin-unpolarized at weak magnetic field and fully polarized at strong field. At intermediate field, a plateau of half the maximal polarization is observed. We study this phenomenon in the frame of composite fermion…
In an ideal two-component two-dimensional electron system, particle-hole symmetry dictates that the fractional quantum Hall states around $\nu = 1/2$ are equivalent to those around $\nu = 3/2$. We demonstrate that composite fermions (CFs)…
We show that in the limit of vanishing bare electron effective mass, and in the presence of particle-hole symmetric disorder (which can be of vanishing strength), the composite fermion Hall conductance is constrained to be $-{1\over…
We construct a new representation of composite fermion wave functions in the lowest Landau level which enables Monte Carlo computations at arbitrary filling factors for a fairly large number of composite fermions, thus clearing the way…
Measurements of the Hall and dissipative conductivity of a strained Ge quantum well on a SiGe/(001)Si substrate in the quantum Hall regime are reported. We find quantum Hall states in the Composite Fermion family and a precursor signal at…
We consider the conductivity tensor for composite fermions in a close to half-filled Landau band in the temperature regime where the scattering off the potential and the trapped gauge field of random impurities dominates. The Boltzmann…
The activation gap $\Delta$ of the fractional quantum Hall states at constant fillings $\nu =2/3$ and 2/5 has been measured as a function of the perpendicular magnetic field $B$. A linear dependence of $\Delta$ on $B$ is observed while…
By developing an algorithm for evaluating the basis states for the composite fermions with negative effective magnetic field, we perform the composite-fermion-diagonalization study for the fully spin-polarized fractional quantum Hall states…
Using acoustic method we study dependences of transverse AC conductance, $\sigma (\omega)$, on magnetic field, temperature and the amplitude of AC electric field in a wide (75 nm) quantum well (QW) structure focusing on the vicinity of the…
We have studied the magnetotransport near Landau level filling factor $\nu = 1/2$ in a GaAs-Al0.3Ga0.7As square quantum well (width 35 nm) in magnetic field up to 42 T and in a temperature range between 50 mK and 1.5 K. In low temperatures…
We report measurements of spin susceptibility of a two-dimensional hole gas confined at an GaAs/AlGaAs interface in density range from 2.8 x 10^10 to 6.5 x 10^10 cm-2. We used the method of spin polarization of carriers in parallel magnetic…
Using a composite fermion picture, we study the lateral transport between two two-dimensional electron gases, at filling factor 1/2, separated by a potential barrier. In the mean field approximation, composite fermions far from the barrier…
In wide GaAs quantum wells where two electric subbands are occupied we apply a parallel magnetic field or increase the electron density to cause a crossing of the two $N=0$ Landau levels of these subbands and with opposite spins. Near the…
We study the critical spin-polarization energy ($\alpha_{\rm C}$) above which fractional quantum Hall states in two-dimensional electron systems confined to symmetric GaAs quantum wells become fully spin-polarized. We find a significant…