15.2 Magnetic Fields
449
R (h/e )
xy
2
R
xx
Fig. 15.21 Hall resistance R xy and magnetoresistance R xx of a two-dimensional electron system (GaAs/(Al,Ga)As
heterostructure) of density n = 2.33 × 10 11 cm −2 at a temperature of 85 mK, versus magnetic field B. Numbers identify
the filling factor ν, which indicates the degree to which the sequence of Landau levels is filled with electrons. Plateaus
are due to the integral (ν = i) quantum Hall effect (IQHE) and fractional (ν = p/q) quantum Hall effect (FQHE).
Adapted from [1480], reprinted with permission, ©1990 AAAS
(a)
(a)
(b)
(b)
Fig. 15.22 Weiss oscillations: a magnetoresistance and b Hall resistance of an antidot lattice (inset in (a)) with pattern
(solid lines) and without pattern (dashed lines) at T = 1.5 K. b Schematic of the different orbits: (‘p’: pinned, ‘d’:
drifting, ‘s’: scattered). Reprinted with permission from [1484], ©1991 APS
449
R (h/e )
xy
2
R
xx
Fig. 15.21 Hall resistance R xy and magnetoresistance R xx of a two-dimensional electron system (GaAs/(Al,Ga)As
heterostructure) of density n = 2.33 × 10 11 cm −2 at a temperature of 85 mK, versus magnetic field B. Numbers identify
the filling factor ν, which indicates the degree to which the sequence of Landau levels is filled with electrons. Plateaus
are due to the integral (ν = i) quantum Hall effect (IQHE) and fractional (ν = p/q) quantum Hall effect (FQHE).
Adapted from [1480], reprinted with permission, ©1990 AAAS
(a)
(a)
(b)
(b)
Fig. 15.22 Weiss oscillations: a magnetoresistance and b Hall resistance of an antidot lattice (inset in (a)) with pattern
(solid lines) and without pattern (dashed lines) at T = 1.5 K. b Schematic of the different orbits: (‘p’: pinned, ‘d’:
drifting, ‘s’: scattered). Reprinted with permission from [1484], ©1991 APS