What are the disliked times for sleep and the reason for this dislike, and what is the time of Duha?

The disliked times for sleep are: after Fajr prayer and after Maghrib prayer. Some medical practitioners dislike the habit of sleeping after Asr prayer (no authentic hadith has been reported concerning this). As for the dislike of returning to sleep for one who woke up during the night, this has been refuted by the actions of the Prophet (PBUH). The Duha time begins from when the sun has risen until it is at its zenith in the middle of the sky.