The energy and photoluminescence spectra of a two-dimensional electron gas in
the fractional quantum Hall regime are studied. The single-particle properties
of reversed-spin quasielectrons (QER's) as well as the
pseudopotentials of their interaction with one another and with Laughlin
quasielectrons (QE's) and quasiholes (QH's) are calculated. Based on the
short-range character of the QER--QER and QER--QE
repulsion, the partially unpolarized incompressible states at the filling
factors ν=114 and 135 are postulated within Haldane's
hierarchy scheme. To describe photoluminescence, the family of bound
h(QER)n states of a valence hole h and n QER's are
predicted in analogy to the found earlier fractionally charged excitons
hQEn. The binding energy and optical selection rules for both families are
compared. The hQER is found radiative in contrast to the dark hQE,
and the h(QER)2 is found non-radiative in contrast to the bright
hQE2.Comment: 9 pages, 6 figure