Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum Dynamics of a Nanomagnet driven by Spin-Polarized Current   A quantum theory of magnetization dynamics of a nanomagnet as a sequence of
scatterings of each electron spin with the macrospin state of the magnetization
results in each encounter a probability distribution of the magnetization
recoil state associated with each outgoing state of the electron. The quantum
trajectory of the magnetization contains the average motion tending in the
large spin limit to the semi-classical results of spin transfer torque and the
fluctuations giving rise to a quantum magnetization noise and an additional
noise traceable to the current noise.

34
The categories of this paper are: chem-ph
32
The categories of this paper are: atom-ph
3
The categories of this paper are: physics
20
The categories of this paper are: acc-phys
7
The categories of this paper are: hep-th
6
The categories of this paper are: astro-ph
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int
0
The categories of this paper are: hep-ph
29
The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex
16
The categories of this paper are: stat