Frequency separation between qubit and chip mode to reduce purcell loss
A system, method, and chip to control Purcell loss are described. The chip includes qubits formed on a first surface of a substrate. The method includes determining frequencies of the qubits, and controlling a separation between the frequencies of the qubits and chip mode frequencies of the chip.
1. A chip with controlled Purcell loss, the chip comprising:
a substrate having a top surface and four edges adjacent and perpendicular to the top surface;
the substrate comprising a circuit and microwave resonators formed on the top surface;
wherein the circuit includes qubits; and
at least one or more of the four edges of the substrate are coated with a metal;
wherein the metal coating changes boundary conditions of the substrate thereby increasing chip mode frequencies to control the Purcell loss of the chip.
2. The chip according to claim 1 , wherein the metal is titanium (Ti).
3. The chip according to claim 2 , wherein the titanium coating is approximately 50 angstroms thick.
4. The chip according to claim 1 , wherein the metal is aluminum (Al).
5. The chip according to claim 4 , wherein the aluminum coating is approximately 500 angstroms thick.
6. The chip according to claim 1 , wherein the substrate is silicon or sapphire.