When I press power button to start only xolo logo appears and after that a blank screen appears and it gets stuck. Please suggest me how can I fix it ?
Welcome to Android Central! Was the phone rooted or unrooted? Did you do anything unusual with it prior to this occurring?
A couple of things to try would be to swap the battery with a new one (if possible), or to remove the SD card (if present).
Also, see if you can boot into Recovery Mode: Xolo Q600 Recovery Mode. If you can, try wiping the cache partition. If that doesn't help, you may have to do a full factory reset, which will wipe the phone.
If you're unable to do any of that, it may be that the hardware or firmware is defective. Contact Xolo or your carrier to see what they can do.