Abstract
In a typical quantum circuit, nonlocal quantum gates are applied to nonproximal qubits. If the underlying physical interactions are short-range (e.g., exchange interactions between spins), intermediate swap operations must be introduced, thus increasing the circuit depth. Here we develop a class of "mediated" gates for spin qubits, which act on nonproximal spins via intermediate ancilla qubits. At the end of the operation, the ancillae return to their initial states. We show how these mediated gates can be used (1) to generate arbitrary quantum states and (2) to construct arbitrary quantum gates. We provide some explicit examples of circuits that generate common states [e.g., Bell, Greenberger-Horne-Zeilinger (GHZ), W, and cluster states] and gates (e.g., √swap, swap, cnot, and Toffoli gates). We show that the depths of these circuits are often shorter than those of conventional swap-based circuits. We also provide an explicit experimental proposal for implementing a mediated gate in a triple-quantum-dot system.
| Original language | English |
|---|---|
| Article number | 062328 |
| Journal | Physical Review A - Atomic, Molecular, and Optical Physics |
| Volume | 86 |
| Issue number | 6 |
| DOIs | |
| Publication status | Published - 26 Dec 2012 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
Cite this
Mediated gates between spin qubits. / Fei, Jianjia; Zhou, Dong; Shim, Yun Pil; Oh, Sangchul; Hu, Xuedong; Friesen, Mark.
In: Physical Review A - Atomic, Molecular, and Optical Physics, Vol. 86, No. 6, 062328, 26.12.2012.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Mediated gates between spin qubits
AU - Fei, Jianjia
AU - Zhou, Dong
AU - Shim, Yun Pil
AU - Oh, Sangchul
AU - Hu, Xuedong
AU - Friesen, Mark
PY - 2012/12/26
Y1 - 2012/12/26
N2 - In a typical quantum circuit, nonlocal quantum gates are applied to nonproximal qubits. If the underlying physical interactions are short-range (e.g., exchange interactions between spins), intermediate swap operations must be introduced, thus increasing the circuit depth. Here we develop a class of "mediated" gates for spin qubits, which act on nonproximal spins via intermediate ancilla qubits. At the end of the operation, the ancillae return to their initial states. We show how these mediated gates can be used (1) to generate arbitrary quantum states and (2) to construct arbitrary quantum gates. We provide some explicit examples of circuits that generate common states [e.g., Bell, Greenberger-Horne-Zeilinger (GHZ), W, and cluster states] and gates (e.g., √swap, swap, cnot, and Toffoli gates). We show that the depths of these circuits are often shorter than those of conventional swap-based circuits. We also provide an explicit experimental proposal for implementing a mediated gate in a triple-quantum-dot system.
AB - In a typical quantum circuit, nonlocal quantum gates are applied to nonproximal qubits. If the underlying physical interactions are short-range (e.g., exchange interactions between spins), intermediate swap operations must be introduced, thus increasing the circuit depth. Here we develop a class of "mediated" gates for spin qubits, which act on nonproximal spins via intermediate ancilla qubits. At the end of the operation, the ancillae return to their initial states. We show how these mediated gates can be used (1) to generate arbitrary quantum states and (2) to construct arbitrary quantum gates. We provide some explicit examples of circuits that generate common states [e.g., Bell, Greenberger-Horne-Zeilinger (GHZ), W, and cluster states] and gates (e.g., √swap, swap, cnot, and Toffoli gates). We show that the depths of these circuits are often shorter than those of conventional swap-based circuits. We also provide an explicit experimental proposal for implementing a mediated gate in a triple-quantum-dot system.
UR - http://www.scopus.com/inward/record.url?scp=84871768247&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84871768247&partnerID=8YFLogxK
U2 - 10.1103/PhysRevA.86.062328
DO - 10.1103/PhysRevA.86.062328
M3 - Article
AN - SCOPUS:84871768247
VL - 86
JO - Physical Review A - Atomic, Molecular, and Optical Physics
JF - Physical Review A - Atomic, Molecular, and Optical Physics
SN - 1050-2947
IS - 6
M1 - 062328
ER -