Low overhead Clifford gates from joint measurements in surface, color, and hyperbolic codes*

One of the most promising routes towards fault-tolerant quantum computation utilizes topological quantum error correcting
codes, such as the Z₂ surface code. Logical qubits can be encoded in a variety of ways in the surface code. However proposed fault-tolerant implementations of the Clifford group in these schemes are limited and often require unnecessary overhead. In this work, we show that within any encoding scheme for the logical qubits, we can fault-tolerantly implement the full Clifford group by using joint measurements involving a single appropriately encoded logical ancilla. This allows us to provide new low overhead implementations of the full Clifford group in surface codes as well as color codes. It also provides the first proposed implementations of the full Clifford group in hyperbolic codes. We further use our methods to propose state-of-the art encoding schemes for small numbers of logical qubits. To our knowledge, this is the optimal proposal to date, and thus may be useful for demonstration of fault-tolerant logical gates in small near-term quantum computers.