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9 votes
Accepted

Is there a classical limit to quantum computing?

In simpler terms your question is: if noise/decoherence keeps entering the computation, how can a big computation possibly survive? The key concept you're missing is quantum error correction, which ...
Craig Gidney's user avatar
8 votes

Scalability of ion trap quantum computers

You may want to check out this Schaetz et al, Reports on Progress in Physics of 2012 "Experimental quantum simulations of many-body physics with trapped ions" (alternate link in semanticscholar). In ...
agaitaarino's user avatar
  • 3,827
6 votes

Scalability of ion trap quantum computers

While I’m not an experimentalist, and have not studied these systems in any great depth, my (crude) understanding is the following: In ion traps you (more or less) have to trap the ions in lines. ...
DaftWullie's user avatar
  • 58.8k
4 votes
Accepted

What do the numbers mean in the elements used in ion traps?

The numbers you are seeing are labeling the isotope, not the charge. For example, they are specifying the isotope of calcium that has 43 nucleons. Since calcium by definition has 20 protons, this ...
Quantum Mechanic's user avatar
3 votes
Accepted

(When) must the ground state of a frustrated Hamiltonian be entangled?

In the Ising model, I don't think frustration is the key feature. Let's start with an arbitrary Ising model with no transversal field. (I'll let you have arbitrary interactions, and arbitrary ...
DaftWullie's user avatar
  • 58.8k
3 votes

Comparing technical limitations of major quantum computing approaches

For a general overview about hardware and the difficulties they present, I recommend section three of Quantum Computing: An Overview Across the System Stack. Another good introduction would be Quantum ...
epelaez's user avatar
  • 2,895
3 votes
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Is there any company trying out ion trap qubits?

IonQ, Honeywell, and Infineon Technologies (list here). From my understanding, IonQ and Honeywell seem to be leading in the trapped ion space
C. Kang's user avatar
  • 1,756
2 votes

How can one trapped ion physically represent quantum states?

The ion states are the different energy states of the ion. These different energy states can be denoted with the total spin of the ion and the phonon levels of the ion. If we look at a Helium atom ...
Peter-Jan's user avatar
  • 1,549
2 votes

Does Stim support the Mølmer–Sørensen gate?

Stim does support the Molmer–Sorensen gate, but it's not called MS. It's called SQRT_XX. The name comes from the fact that the ...
Craig Gidney's user avatar
2 votes

Modular exponentiation quantum circuit design for Shor's algorithm

The references below explain the construction of modular exponentiation circuit. I also attempt to implement the circuit accordingly in https://github.com/thyung/qiskit_factorization using qiskit and ...
thyung's user avatar
  • 21
2 votes

Modular exponentiation quantum circuit design for Shor's algorithm

There are many quantum implementations of modular exponentiation to choose from depending on whether you want to optimize qubit count vs time and other similar tradeoffs. However, for the method ...
Joseph Geipel's user avatar
1 vote

Cirac-Zoller CNOT gate implemented by Schmidt-Kaler

Your formula for $R_2(\pi/2,\pi)$ is incorrect: The resulting matrix is not unitary (but rather rank 1). (There should be +1 in the top right corner.)
Norbert Schuch's user avatar
1 vote

Simultaneous computational basis measurement

Before we explain how ion traps and superconducting qubits are measured, let's clarify what's meant by a basis, as that might reduce some confusion about simultaneous measurements. Following up on the ...
Mark Spinelli's user avatar
1 vote
Accepted

High-weight errors from ion trap crosstalk

Before going further, I think it is worth pointing out that trapped ions have any-to-any rather than all-to-all coupling. With maybe a few exceptions, no one is doing anything more than two qubit ...
Dr. T. Q. Bit's user avatar
1 vote

What is the elementary gate set for ion-trap quantum computers?

In terms of single qubit gates, ion traps rather easily can do any arbitrary rotation on the Bloch sphere - those are all straightforward to do. For two qubit gates, most trapped ion systems use a ...
Dr. T. Q. Bit's user avatar

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