Tootfinder

All you need is controlled-V: universality of a standard two-qubit gate by catalytic embedding
Robin Kaarsgaard
https://arxiv.org/abs/2509.07578 https://ar…

All you need is controlled-V: universality of a standard two-qubit gate by catalytic embedding
We present an encoding that renders the controlled-V gate (also known as controlled-$\sqrt{X}$) computationally universal in isolation. Specifically, we show that this gate can simulate the universal Clifford+Toffoli gate set with at most two clean auxiliary qubits and a constant overhead in gate count, and that an additional auxiliary qubit suffices to simulate Clifford+T. Our result settles an open question on the expressiveness of De Vos' gate set based on Negators, and shows that the two-qu…

Toffoli and C$^\text{n}$NOT (n$>2$) gates in a neutral-atom platform using Rydberg coupling and dark state resonances
Sinchan Snigdha Rej, Bimalendu Deb
https://arxiv.org/abs/2507.02531

Toffoli and C$^\text{n}$NOT (n$>2$) gates in a neutral-atom platform using Rydberg coupling and dark state resonances
We propose a protocol for realizing a Toffoli gate using neutral-atom qubits in optical tweezers. Two ground-state hyperfine levels of the atoms are considered as qubit states. Our method relies on the strong and long-range interactions between atoms due to Rydberg excitations and the occurrence of dark states in the target qubit, with both control and target qubits being individually addressed with laser pulses. Our gate protocol enables precise control over the quantum states of individual qu…

Jenga-Krotov algorithm: Efficient compilation of multi-qubit gates for exchange-only qubits
Jiahao Wu, Guanjie He, Wenyuan Zhuo, Quan Fu, Xin Wang
https://arxiv.org/abs/2507.12448

Jenga-Krotov algorithm: Efficient compilation of multi-qubit gates for exchange-only qubits
Exchange-only (EO) qubits, implemented in triple-quantum-dot systems, offer a compelling platform for scalable semiconductor-based quantum computing by enabling universal control through purely exchange interactions. While high-fidelity single- and two-qubit gates have been demonstrated, the synthesis of efficient multi-qubit operations -- such as the Toffoli gate -- remains a key bottleneck. Conventional gate decompositions into elementary operations lead to prohibitively long and error-prone …