This is a follow-up question to @heather's answer to the question : Why must quantum computers be kept near absolute zero?
What I know:
Superconducting quantum computing: It is an implementation of a quantum computer in a superconducting electronic circuit.
Optical quantum computing: It uses photons as information carriers, and linear optical elements to process quantum information, and uses photon detectors and quantum memories to detect and store quantum information.
Classical computation models rely on physical implementations consistent with the laws of classical mechanics. It is known, however, that the classical description is only accurate for specific cases, while the more general description of nature is given by the quantum mechanics. Quantum computation studies the application of quantum phenomena, that are beyond the scope of classical approximation, for information processing and communication. Various models of quantum computation exist, however the most popular models incorporate the concepts of qubits and quantum gates. A qubit is a generalization of a bit - a system with two possible states, that can be in a quantum superposition of both. A quantum gate is a generalization of a logic gate: it describes the transformation that one or more qubits will experience after the gate is applied on them, given their initial state. The physical implementation of qubits and gates is difficult, for the same reasons that quantum phenomena are hard to observe in everyday life. One approach is to implement the quantum computers in superconductors, where the quantum effects become macroscopic, though at a price of extremely low operation temperatures.
This does make some sense! However, I was looking for why optical quantum computers don't need "extremely low temperatures" unlike superconducting quantum computers. Don't they suffer from the same problem i.e. aren't the quantum phenomena in optical quantum computers difficult to observe just as for superconducting quantum computers? Are the quantum effects already macroscopic at room temperatures, in such computers? Why so?
I was going through the description of Linear optical quantum computing on Wikipedia, but found no reference to "temperature" as such.