What is a stronger topical antibiotic cream than those used in Neosporin for ulcerative wound care.

Wrong question. NO antibiotic is useful for wound care. Neosporin is useless. Studies of surgical wounds comparing antibiotics to vaseline or Aquaphor showed no benefit from bacitracin or neosporin. Use of topical antibiotics caused allergic reactions, impaired wound healing, and promoted emergence of resistant bacteria such as MRSA. Care of a wound is determined by its location and size and cause.
BETTER, not stronger. Your question likely stems from a wound that is not getting better, despite neosporin. Maybe neosporin is the the BEST antibiotic for that infection (it is good for most, but not all, so you may have to identify the actual infection). But an infection may not even be the problem (in which case no antibiotic will be any better). Experienced wound therapist can identify other impediments to healing.