  Superconducting devices with broken time-reversal and spatial-inversion
symmetries can exhibit novel superconducting phenomena. The observation of
superconducting diode effects, which is applicable for dissipationless
rectification, provides information on the breaking of such symmetries. We
experimentally study a Josephson junction (JJ) coupled to another adjacent JJ
as a new system exhibiting the superconducting diode effect. We demonstrate
that the observed superconducting diode effect can be controlled non-locally
based on the phase difference with the adjacent JJ. These results indicate that
the time-reversal and spatial-inversion symmetries of a JJ are broken by the
coherent coupling to an adjacent JJ, and this enables the engineering of novel
superconducting phenomena mediated by coherent coupling among JJs and
development of their applications for superconducting diode devices.
