Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Robust quantum gates for singlet-triplet spin qubits using composite
  pulses   We present a comprehensive theoretical treatment of SUPCODE, a method for
generating dynamically corrected quantum gate operations, which are immune to
random noise in the environment, by using carefully designed sequences of soft
pulses. SUPCODE enables dynamical error suppression even when the control field
is constrained to be positive and uniaxial, making it particularly suited to
counteracting the effects of noise in systems subject to these constraints such
as singlet-triplet qubits. We describe and explain in detail how to generate
SUPCODE pulse sequences for arbitrary single-qubit gates and provide several
explicit examples of sequences that implement commonly used gates, including
the single-qubit Clifford gates. We develop sequences for noise-resistant
two-qubit gates for two exchanged-coupled singlet-triplet qubits by cascading
robust single-qubit gates, leading to a 35% reduction in gate time compared to
previous works. This cascade approach can be scaled up to produce gates for an
arbitrary-length spin qubit array, and is thus relevant to scalable quantum
computing architectures. To more accurately describe real spin qubit
experiments, we show how to design sequences that incorporate additional
features and practical constraints such as sample-specific charge noise models
and finite pulse rise times. We provide a detailed analysis based on randomized
benchmarking to show how SUPCODE gates perform under realistic $1/f^\alpha$
noise and find a strong dependence of gate fidelity on the exponent $\alpha$,
with best performance for $\alpha>1$. Our SUPCODE sequences can therefore be
used to implement robust universal quantum computation while accommodating the
fundamental constraints and experimental realities of singlet-triplet qubits.

22
The categories of this paper are: chao-dyn
28
The categories of this paper are: alg-geom
11
The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
32
The categories of this paper are: atom-ph
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an
9
The categories of this paper are: nlin