Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Transverse mode-encoded quantum gate on a silicon photonic chip   As an important degree of freedom (DoF) in integrated photonic circuits, the
orthogonal transverse mode provides a promising and flexible way to increasing
communication capability, for both classical and quantum information
processing. To construct large-scale on-chip multimode multi-DoF quantum
systems, a transverse mode-encoded controlled-NOT (CNOT) gate is necessary.
Here, through design and integrate transverse mode-dependent directional
coupler and attenuators on a silicon photonic chip, we demonstrate the first
multimode implementation of a two-qubit quantum gate. With the aid of state
preparation and analysis parts, we show the ability of the gate to entangle two
separated transverse mode qubits with an average fidelity of $0.89\pm0.02$ and
the achievement of 10 standard deviations of violations in the quantum
nonlocality verification. In addition, a fidelity of $0.82\pm0.01$ was obtained
from quantum process tomography used to completely characterize the CNOT gate.
Our work paves the way for universal transverse mode-encoded quantum operations
and large-scale multimode multi-DoF quantum systems.

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The categories of this paper are: dg-ga
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
32
The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
18
The categories of this paper are: econ