If you can afford the app fees I'd apply anyway, the worst that can happen is they say no. If you decide to wait though, your options can be different depending on your location. In general however, you can try becoming a volunteer researcher, or if you're lucky a paid researcher, with one of the profs at your school or one near by. Enroll as a non-degree seeking student and take some grad classes, nothing too demanding if you're doing extensive amounts of research, but something to add to your experience. If you're near a national lab, or a university partnered with one that offers on-site jobs, you could give that a shot too. Basically, I'd apply none the less but I understand if finances restrict you. Then I'd wait and see, and if it's rejections across the board which shouldn't happen if you pick your schools wisely, then exploit any resources and connections you have in your own physics department to get more experience between now and the next admissions cycle. Personally, I'd start with my favorite prof and the one who knows me the best, explain the situation which they should be semi-aware of as they're likely to be one of your recommending profs. Just say that you're going to work on your app strength to give it another go, and that you'd like to get involved with some more research, paid preferably, unpaid if need be (again if you can afford to be unpaid) do they know anything or can they help in any way.