**The Perfect State Transfer Graph Limbo.** / Kay, Alastair.

Research output: Contribution to journal › Article

Submitted

**The Perfect State Transfer Graph Limbo.** / Kay, Alastair.

Research output: Contribution to journal › Article

Kay, A. (2018). The Perfect State Transfer Graph Limbo. Manuscript submitted for publication.

@article{2701394bc59b476ab09de77e5db83d8f,

title = "The Perfect State Transfer Graph Limbo",

abstract = " Perfect state transfer between qubits on a uniformly coupled network, with interactions specified by a graph, has advantages over an engineered chain, such as much faster transfer times (independent of the distance between the input and output vertices). This is achieved by many couplings working in parallel. The trade-offs seem to be the need for increasing connectivity between qubits, and a large number of vertices in the graph. The size of existing graph constructions scale exponentially in the transfer distance, making these schemes impractical over anything but the shortest distances. This prompts the question of {"}How low can you go?{"} for the size of the graph achieving a particular transfer distance. In this paper, we present reductions in the vertex count required, although the overall scaling with transfer distance remains exponential. We also tighten existing bounds on the required degree of the vertices of the graph. ",

keywords = "quant-ph",

author = "Alastair Kay",

note = "12 pages. v2: eventually got around to thinking about journal submission",

year = "2018",

month = aug,

day = "2",

language = "English",

journal = "Physical Review A",

issn = "1050-2947",

publisher = "American Physical Society",

}

TY - JOUR

T1 - The Perfect State Transfer Graph Limbo

AU - Kay, Alastair

N1 - 12 pages. v2: eventually got around to thinking about journal submission

PY - 2018/8/2

Y1 - 2018/8/2

N2 - Perfect state transfer between qubits on a uniformly coupled network, with interactions specified by a graph, has advantages over an engineered chain, such as much faster transfer times (independent of the distance between the input and output vertices). This is achieved by many couplings working in parallel. The trade-offs seem to be the need for increasing connectivity between qubits, and a large number of vertices in the graph. The size of existing graph constructions scale exponentially in the transfer distance, making these schemes impractical over anything but the shortest distances. This prompts the question of "How low can you go?" for the size of the graph achieving a particular transfer distance. In this paper, we present reductions in the vertex count required, although the overall scaling with transfer distance remains exponential. We also tighten existing bounds on the required degree of the vertices of the graph.

AB - Perfect state transfer between qubits on a uniformly coupled network, with interactions specified by a graph, has advantages over an engineered chain, such as much faster transfer times (independent of the distance between the input and output vertices). This is achieved by many couplings working in parallel. The trade-offs seem to be the need for increasing connectivity between qubits, and a large number of vertices in the graph. The size of existing graph constructions scale exponentially in the transfer distance, making these schemes impractical over anything but the shortest distances. This prompts the question of "How low can you go?" for the size of the graph achieving a particular transfer distance. In this paper, we present reductions in the vertex count required, although the overall scaling with transfer distance remains exponential. We also tighten existing bounds on the required degree of the vertices of the graph.

KW - quant-ph

M3 - Article

JO - Physical Review A

JF - Physical Review A

SN - 1050-2947

ER -