Questions tagged [experimental-realization]
For questions about physical implementations of a quantum algorithm or other quantum information protocol. DO NOT use for questions about simulation or emulation of quantum computers, or cloud-based quantum computing services like the IBM Q Experience.
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Are operators unitary on a real quantum computer?
The question is more from the physical side of quantum computers. Can we say that operators are unitary or due to the NISQ nature, the operator (impact on particles) in reality deviates from this ...
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What is the logical gate speed of a superconducting quantum computer?
What is the logical gate speed of a photonic quantum computer? says
In a simple world the speed of a photonic quantum computer would just be the speed at which it’s possible to make small (fixed ...
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How to do a Bell state measurement on encoded qubits fault tolerantly?
Experimentally how do you do a Bell state measurement? Is it just a CNOT and a Hadamard and then a measurement in the computational basis? Or is it even simpler than that because it is easy to measure ...
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Will logical clock cycle time be a limiting factor for quantum computations?
Fault-tolerant quantum computation promises to strongly suppress the errors by scaling up the size of the systems. Right now, different physical implementations of proto quantum computers have very ...
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Why do Surface codes generate so much measurement data?
I read in the Sparse Blossom paper: "A surface code superconducting quantum computer with a million physical qubits will generate
measurement data at a rate of around 1 terabit per second".
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Is there a term for fault-tolerance of logical gates that depends on the underlying hardware?
Is there a notion of fault-tolerance of logical gates that also accounts for the underlying hardware? If so, how is this notion / term called?
An example:
A possible choice of logical basis states in ...
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What could be intermediate steps towards a fully fault-tolerant quantum algorithm with added value for each step?
Starting from an algorithm without any error correction or detection, what incremental improvements can be made towards fully fault-tolerant encoding and operation?
It seems that fault-tolerant error ...
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Experimental implementation of addition on a quantum computer
Addition is a basic arithmetic routine, but it has been surprisingly difficult to find a reference that experimentally implements it, despite it existing on various tutorials such as qiskit. Is there ...
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How to physically implement a CNOT gate with a photon and a cold atom?
If I have qubits in the same platform (superconducting, photon or cold atoms), the implementation of CNOT gates is relatively well-known. However, if I have a photon and a cold atom, how am I supposed ...
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For QC hardware, is there an usecase/need for higher quality semiconductor crystal?
Is there a requirement for higher-quality semiconductor material? For example, is higher purity required? I could imagine, that the quality of germanium, which is used for some Qubit implementations, ...
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What the stern-gerlach experiment would look like for tensor-product observable?
The experiment says, that having the $Z$ observable and a qubit, we can have outcomes $+1$ and $-1$. Suppose we have more than one qubit, and build an observable like $O = 3Z_1 + 5Z_3 + 2Z_4$. It also ...
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What is the definition of physical gate error rate?
The fidelity of two quantum states $\rho$ and $\sigma$ is a well-defined (up to discussions about a square):
$$
F(\rho, \sigma) = \text{Tr}\left( \sqrt{ \sqrt{\rho} \sigma \sqrt{\rho}}\right)^2.
$$
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In what limit does the estimator sample variance converge to the Cramer-Rao bound?
In the context of a single phase estimation problem of a quantum photonics experiment (related post). For example consider a 3-photon quantum circuit (such as the Mach-Zehnder which depends on some ...
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Fisher information from likelihood function for discrete quantum case
In the context of a single phase estimation problem of a quantum photonics experiment. For example consider a 3-photon quantum circuit (such as the Mach-Zehnder which depends on some phase shift ...
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Can a single qubit gate fidelity be benchmarked through XEB (Cross-Entropy Benchmarking)?
I'm currently investigating two qubit Cross-Entropy benchmarking and was able to simulate the decay curve that one would get in experiment when doing cycles for the case of two qubits (random single ...
