Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic control of large room-temperature polarization   Numerous authors have referred to room-temperature magnetic switching of
large electric polarizations as The Holy Grail of magnetoelectricity.We report
this long-sought effect using a new physical process of coupling between
magnetic and ferroelectric relaxor nano-regions. Here we report magnetic
switching between the normal ferroelectric state and the ferroelectric relaxor
state. This gives both a new room-temperature, single-phase, multiferroic
magnetoelectric, PbZr0.46Ti0.34Fe0.13W0.07O3, with polarization, loss (<4%),
and resistivity (typically 108 -109 ohm.cm) equal to or superior to BiFeO3, and
also a new and very large magnetoelectric effect: switching not from +Pr to
negative Pr with applied H, but from Pr to zero with applied H of less than a
Tesla. This switching of the polarization occurs not because of a conventional
magnetically induced phase transition, but because of dynamic effects:
Increasing H lengthens the relaxation time by x500 from <200 ns to >100 ?s, and
it couples strongly the polarization relaxation and spin relaxations. The
diverging polarization relaxation time accurately fits a modified Vogel-Fulcher
Equation in which the freezing temperature Tf is replaced by a critical
freezing field Hf that is 0.92 positive/negative 0.07 Tesla. This field
dependence and the critical field Hc are derived analytically from the
spherical random bond random field (SRBRF) model with no adjustable parameters
and an E2H2 coupling. This device permits 3-state logic (+Pr,0,negative Pr) and
a condenser with >5000% magnetic field change in its capacitance.

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The categories of this paper are: dg-ga
3
The categories of this paper are: physics
16
The categories of this paper are: stat
32
The categories of this paper are: atom-ph
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat
25
The categories of this paper are: patt-sol
2
The categories of this paper are: math
7
The categories of this paper are: hep-th
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
8
The categories of this paper are: hep-ex
29
The categories of this paper are: funct-an
1
The categories of this paper are: cs