Yes, working quantum computers have been developed by several organizations and research institutions. Quantum computing is an active field of research, and scientists have made significant progress in building and operating quantum computers with varying numbers of qubits.
One prominent example is IBM's Quantum Experience, a cloud-based platform that provides access to real quantum hardware. IBM has developed several generations of quantum computers, starting with the IBM Q Experience, which was launched in 2016. Over the years, IBM has continued to improve its quantum systems, and they had developed quantum computers with up to 65 qubits.
Other organizations, such as Google, Microsoft, Rigetti Computing, and IonQ, have also made significant strides in developing quantum computers. For example, Google achieved a major milestone in 2019 called "quantum supremacy" when its quantum computer successfully solved a specific problem that would be practically infeasible for classical computers to solve within a reasonable time frame.
It's important to note that the current quantum computers are still in the early stages of development and face various challenges, such as improving qubit coherence and reducing errors. However, the progress made so far is remarkable, and quantum computers hold the potential for solving certain problems more efficiently than classical computers in the future.
As the field of quantum computing continues to advance, we can expect to see more powerful and capable quantum computers being developed, pushing the boundaries of what is possible in computation and technology.