Error using loadlibrary

Hi… I am working on matlab 2014 and GPU. I want to run cublas functions in mex files but I found following error

Error using loadlibrary (line 422)
There was an error loading the library “libcublas”
The specified module could not be found.
Caused by:
Error using loaddefinedlibrary
The specified module could not be found.

please help me