Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Engineering Quantum Confinement in Semiconducting van der Waals
  Heterostructure   Spatial confinement and manipulation of charged carriers in semiconducting
nanostructures are essential for realizing quantum electronic devices.
Gate-defined nanostructures made of two-dimensional (2D) semiconducting
transition metal dichalcogenides (TMDCs) have the potential to add a unique
additional control of quantum degrees of freedom owing to valley-spin locking
of confined carriers near the band edges. However, due to prevailing
inhomogeneities in the conducting channels, it has been difficult to realize
quantum confinement in 2D TMDCs with well-controlled tunnel-coupling strength.
Here we demonstrate quantum transport in lateral gate-defined 2D electron
quantum dots formed in atomically thin TMDC heterostructures. Utilizing
micro-fabricated local contact gates, encapsulation in 2D dielectrics and light
illumination at low temperatures, we show that the quality of TMDC 2D electron
gases (2DEGs) can be improved, rendering them suitable for mesoscopic quantum
transport measurements. We observe quantized conductance in quantum point
contact (QPC) channels controlled by gate-tunable confinement. We also
demonstrate single electron transport in TMDC quantum dots (QD) with tunable
tunnel-coupling. Our observation holds promise for the quantum manipulation of
spin and valley degrees of freedom in engineered TMDC nanostructures, enabling
versatile 2D quantum electronic devices.

16
The categories of this paper are: stat
3
The categories of this paper are: physics
6
The categories of this paper are: astro-ph
5
The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas
8
The categories of this paper are: hep-ex
19
The categories of this paper are: eess
17
The categories of this paper are: q-fin
2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
7
The categories of this paper are: hep-th
23
The categories of this paper are: solv-int
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The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph
21
The categories of this paper are: adap-org
32
The categories of this paper are: atom-ph