Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Experimental Quantum Switching for Exponentially Superior Quantum
  Communication Complexity   Finding exponential separation between quantum and classical information
tasks is like striking gold in quantum information research. Such an advantage
is believed to hold for quantum computing but is proven for quantum
communication complexity. Recently, a novel quantum resource called the quantum
switch---which creates a coherent superposition of the causal order of events,
known as quantum causality---has been harnessed theoretically in a new protocol
providing provable exponential separation. We experimentally demonstrate such
an advantage by realizing a superposition of communication directions for a
two-party distributed computation. Our photonic demonstration employs
$d$-dimensional quantum systems, qudits, up to $d=2^{13}$ dimensions and
demonstrates a communication complexity advantage, requiring less than $(0.696
\pm 0.006)$ times the communication of any causally ordered protocol. These
results elucidate the crucial role of the coherence of communication direction
in achieving the exponential separation for the one-way processing task, and
open a new path for experimentally exploring the fundamentals and applications
of advanced features of indefinite causal structures.

10
The categories of this paper are: q-bio
19
The categories of this paper are: eess
0
The categories of this paper are: hep-ph
1
The categories of this paper are: cs
26
The categories of this paper are: bayes-an
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
18
The categories of this paper are: econ
9
The categories of this paper are: nlin
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an