[vectorEQ]

a bit off topic shot in the dark here, but no one seems to be able to tell me so far. what kind of machine code a quantum computer would execute. is it a instruction set like any computer or does it contain a lot of weirdness (instructions mapping to insane kind of micro-op sequences or something?) is there any information out on that topic at all? i am assuming it would still be mapping some electrical 1/0 kind of values to machine code up to higher level languages, but the concept just makes my brain fart a bit when i think about it. it would be super interesting to learn about or read up on

[jfitzsimons]

Quantum processors don't have the same gate sets as are used in conventional computers, since they can be in superpositions rather than in just the 0 and 1 state. Instead of NAND gates, a universal set of quantum gates will include a gate capable of producing quantum mechanical interference, such as a Hadamard gate. Almost all programming languages are currently at this gate level, often implemented through Python or another high-level language which you can use to build the circuit (e.g. IBM Qiskit, or Rigetti PyQuil). Our focus has been on building higher level languages to get to a point where the level of abstraction is such that the same code can be compiled for both conventional and quantum processors, which is not something that can be done with existing tools without resorting to the extremely inefficient direct simulation of quantum processors. The exact output we shoot for depends on the processor. For the Rigetti processors, for example, the native set of gates are limited to specific single qubit rotations and specific two-bit gates (CZ or parameterised XY gates). It is sufficient to construct a program using these gates, although we implement a transpiler to convert between any universal set of gates. For various reasons (usually to combat noise or increase performance of the processor) it is sometimes useful to be able to compile to lower level operations. In particular, for most quantum processors gate operations are implemented using laser/microwave/radiowave pulses, and so ultimately you aim to a sequence of such pulses. Being able to tweak the shape, phase, frequency and duration of such pulses is important for maximising the performance of the device. This is usually done to minimise error rates, but can also be done in an. attempt to realise faster logic gates etc.

[vectorEQ]

Thanks a lot for the response. Even though admittedly I can hardly comprehend what it means, it certainly gives me finally some topics and concepts to dive a bit deeper into to try and get my head around such a complicated topic, especially your points on the logic gates used. i've always looked at it more from a down to up approach, but this explains exactly why that has gotten me no where so far. thanks a lot. :D