PURIS CRITERION AND HIGHER-ORDER SQUEEZING

Recently, Puri revisited the usual uncertainty relation arguments. Utilizing a well-known and sharpened version of the uncertainty relation, he has proposed an alternative squeezing criterion for the case of noncanonical operators. We investigated this in the hope that Puri's proposal might allow one to define a higher-order squeezing criterion that would avoid an anomaly found with the standard Hong-Mandel (HM) scheme, i.e., the possibility of simultaneous-quadrature squeezing. However, it is found that higher-order squeezing based on Puri's squeezing criterion has what one might judge to be an even worse and unphysical defect than the HM scheme, in that even at the squeezing ''trigger level,'' squeezing in one quadrature is necessarily accompanied by considerable antisqueezing in the other quadrature. © 1995 The American Physical Society.