  Which-path information of a quantum particle in interferometers is the key to
infer the past of quantum particle. It arises many extensive discussions
including quantum complementarity and path-visibility relation. The basic of
these discussions are the description, detection and control of which-path
information. In this article, we focus on the investigation of multidimensional
which-path information in nested Mach-Zehnder interferometer. A general
expression of which-path information is given and can be partially extracted by
different detection method. Further analysis shows that the which-path
information can be controlled by the phase differences and beam splitting
ratios between the arms of nested Mach-Zehnder interferometer. Moreover, a new
which-path information elimination phenomenon has been predicted and
demonstrated experimentally. Our work can help to understand the physics of
quantum particles, potentially apply to quantum information process and quantum
metrology.
