Air carrier Captain reported a tight vector to final approach which resulted in an unstable approach and a low altitude alert from the Tower. The Captain instructed the First Officer to level off and re-intercept the glideslope to a landing.

Narrative

Approach Control gave us a vectored base leg that was almost directly to the final approach fix. It left very little room to capture the LOC and get configured and slowed and then capture the GS.The First Officer (FO) is fresh new and just consolidating and still learning the airplane in a line flying setting.As we neared the FAF I was working the radio; monitoring his flying and giving him suggestions to make a smooth and stable approach given the circumstances.We captured the LOC just outside the FAF but were too high to capture the GS so I told him to descend to try and get on the GS. We descended too fast and were under the GS as I accepted and read back the landing clearance. Tower gave us a low altitude alert and I responded that we were correcting.I told the FO to level off and we stayed around 900 feet until GS capture and continued the approach to a landing.Cause: Bad vectorInexperienced FOCaptain increased workloadA few weeks ago at MSY to Runway 11 I experienced the same bad vector almost directly to the FAF.I should have asked for a longer downwind today.