12 votes
Accepted

What is the purpose of a quantum RAM in quantum algorithms?

This is discussed in chapter 5 of Ciliberto et al.. The purpose of most quantum(-enhanced) machine learning algorithms is to speed-up the processing of classical data over what is possible with ...
glS's user avatar
  • 22.8k
12 votes
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What protocols have been proposed to implement quantum RAMs?

A good summary on the current state of QRAM (as of 2017) can be found in this paper, and a comparison of it with classical methods can be found in this talk. The Giovannetti type "bucket brigade" QRAM ...
James Wootton's user avatar
10 votes

Quantum memory assisting classical memory

In summary, no. If you think about it, this makes sense. When measuring a quantum system with $n$ qubits, you get $n$ bits of information. the $2^n$ figure exists only when the system is in ...
Auden Young's user avatar
  • 3,369
6 votes
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State of the art in quantum memory

Unfortunately the state of the technology regarding memories is not as developed as you seem to expect. When we talk about a memory, we think of a device that can store information for an infinite ...
M. Stern's user avatar
  • 2,492
4 votes

Are bucket-brigate (q)RAM architectures also advantageous in the classical case?

They say that this scheme requires to throw $O(N)$ switches for each memory call, but I don't understand why is this the case. From the above, it would seem that one just needs to throw $O(\log_2(N))...
James Wootton's user avatar
4 votes

Can quantum computers handle 'big' data?

It's not so much a matter of big data, but that of saving data. Quantum storage is still (much like the rest of the field) in its infancy. (Take what I write with a grain of salt. It's likely to ...
ItamarG3's user avatar
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3 votes
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Resources for QRAM implemented as a subroutine for quantum algorithm

If you are looking for implementations of quantum memories, you can find a few in this QRAM library for Q#. I am not quite sure what you mean by the bucket brigade protocol is not able to readout ...
Dr. Sarah Kaiser's user avatar
3 votes
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Qubit demands of Grover's Algorithm

The ancilla shouldn't be entangled with the main register after every iteration and the same ancilla qubit should be able to be reused for every iteration, in fact the ancilla's state shouldn't change ...
Joseph Geipel's user avatar
3 votes
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What is the state of the art on Quantum Random Access Memories?

According to comment provided by user gIS, there was no progress in implementing qRAM as proposed in the paper. However, some additional information on qRAM physical implementation can be found on ...
Martin Vesely's user avatar
3 votes

Q-means, QRAM and how it helps algorithmic speedup

Partial answer (why qRAM is useful) Currently, quantum computers do not have an operational memory. Quantum processor is composed of qubits which can be considered to be an elementary memory. However, ...
Martin Vesely's user avatar
3 votes

How to store qubits while preserving Heisenberg's uncertainty principle?

Your question revolves implicitly around the concept of quantum decoherence and how to protect real-world implementations of qubits from it for a long time. This is an incredibly general problem, and ...
agaitaarino's user avatar
  • 3,747
3 votes

Can a stored programming model be applied to a Quantum Computer?

Yes, you can encode a program into your qubits in exactly the same way you'd encode a program into bits and then run circuits that interpret the program. One might hope that you could encode the ...
Craig Gidney's user avatar
  • 32.3k
2 votes

Are bucket-brigate (q)RAM architectures also advantageous in the classical case?

An answer to this question seems to have been given by the same authors, in a different follow-up paper which I hadn't seen before. In [1], the authors write (emphasis mine): A classical RAM that ...
glS's user avatar
  • 22.8k
2 votes

How will quantum computers access large amounts of storage?

Typically, quantum search algorithm searches through a very large solution spaces that can represented by logarithmic scale of data, not directly over huge amount of data. An example is travelling ...
czwang's user avatar
  • 849
2 votes
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How will quantum computers access large amounts of storage?

Qiskit and other programming languages allow to write a hybrid algorithms, i.e. combination of classical and quantum algorithm. Inputs to quantum algorithm can be pre-processed on classical computer ...
Martin Vesely's user avatar
2 votes

How does quantum memory work using atoms?

You seem to be thinking about "quantum memory" like it is one specific thing and there is only one specific way it can happen. In reality, what you describe is a valid notion of quantum memory. ...
CARNEGIE's user avatar
  • 151
2 votes

Does quantum computing take more computer memory (storage) than classical computing?

Bits and qubits are logical concepts. The comparison comes in the logic. Specifically, a Hilbert space is more general than a Boolean space. To answer your question, one need to, first, consider a ...
Daniele Cuomo's user avatar
2 votes
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Is it possible to use quantum state to store and read information without destorying it?

Reading information from a quantum system is possible only via a measurement, which mathematically can be described as applying a Hermitian operator (also called "observable") on the Hilbert ...
Ohad's user avatar
  • 1,654
1 vote

Qubit demands of Grover's Algorithm

There is an explicit example of solving constraint satisfaction problems by the Grover's algorithm. It needs only a single ancillary spin. Although strong entanglement is generated during physical ...
Nik's user avatar
  • 31
1 vote

Q-means, QRAM and how it helps algorithmic speedup

I think the point is that many quantum algorithms prove/are believed to be efficient to process data when said data is encoded in a quantum state. An easy example of this being Grover, which produces (...
glS's user avatar
  • 22.8k

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