# Algorithmic cooling and scalable NMR quantum computers

@article{Boykin2001AlgorithmicCA, title={Algorithmic cooling and scalable NMR quantum computers}, author={P. Oscar Boykin and Tal Mor and Vwani P. Roychowdhury and Farrokh Vatan and Rutger Vrijen}, journal={Proceedings of the National Academy of Sciences of the United States of America}, year={2001}, volume={99}, pages={3388 - 3393} }

We present here algorithmic cooling (via polarization heat bath)—a powerful method for obtaining a large number of highly polarized spins in liquid nuclear-spin systems at finite temperature. Given that spin-half states represent (quantum) bits, algorithmic cooling cleans dirty bits beyond the Shannon's bound on data compression, by using a set of rapidly thermal-relaxing bits. Such auxiliary bits could be implemented by using spins that rapidly get into thermal equilibrium with the environment…

## 107 Citations

### Improved algorithmic cooling for scalable NMR quantum computers

- Physics, Computer ScienceSPIE Defense + Commercial Sensing
- 2006

This preliminary work studies the optimality of purification as a tradeoff between the number of cooled spins and the closeness of their quantum state to the ideal pure state.

### A pr 2 01 4 Experimental Heat-Bath Cooling of Spins

- Physics
- 2019

Algorithmic cooling (AC) is a method to purify quantum systems, such as ensembles of nuclear spins, or cold atoms in an optical lattice. When applied to spins, AC produces ensembles of highly…

### Optimal Algorithmic Cooling of Spins

- Computer ScienceUC
- 2007

The "all-bonacci" algorithm is presented, which appears to reach the maximal degree of cooling obtainable by the optimal AC approach, and several new exhaustive cooling algorithms, such as the Tribonacci and k-honacci algorithms are introduced.

### Cooling of Spins via Quantum Data Compression

- Physics, Computer Science2007 10th Canadian Workshop on Information Theory (CWIT)
- 2007

This work studies how classical data compression codes can be used to design cooling algorithms and utilizes fixed-rate block compression codes for long molecules and variable-rate lossless compression codesfor short molecules and provides a rudimentary analysis of cooling performance for both short and long molecules.

### Heat Bath Algorithmic Cooling with Spins: Review and Prospects

- Physics
- 2016

Application of multiple rounds of Quantum Error Correction (QEC) is an essential milestone towards the construction of scalable quantum information processing devices. The requirements for multiple…

### Paramagnetic materials and practical algorithmic cooling for NMR quantum computing

- PhysicsSPIE Defense + Commercial Sensing
- 2003

Algorithmic cooling is a method devised by Boykin, Mor Rowchodhury, Vatan and Vrijen (PNAS Mar '02) for initializing NMR systems in general and NMR quantum computers in particular. The algorithm…

### Strong algorithmic cooling in large star-topology quantum registers

- Physics
- 2017

We envisage a star-topology quantum register, wherein a central computation qubit is symmetrically surrounded by a set of reset qubits. The reset qubits cool the computation qubit by transferring its…

### Algorithmic Cooling of Spins: A Practicable Method for Increasing Polarization

- Physics
- 2004

An efficient technique to generate ensembles of spins that are highly polarized by external magnetic fields is the Holy Grail in Nuclear Magnetic Resonance (NMR) spectroscopy. Since spin-half nuclei…

### Hyperfine spin qubits in irradiated malonic acid: heat-bath algorithmic cooling

- PhysicsQuantum Inf. Process.
- 2015

By accurately determining the full spin Hamiltonian and performing realistic algorithmic simulations, it is shown that an experimental demonstration of heat-bath algorithmic cooling beyond the Shannon bound is feasible in both three-qu bit and five-qubit variants of this spin system.

### Algorithmic Cooling of Nuclear Spin Pairs using a Long-Lived Singlet State.

- Physics
- 2019

Algorithmic cooling methods manipulate an open quantum system in order to lower its temperature below that of the environment. We show that significant cooling is achieved on an ensemble of spin-pair…

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